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FERNANDEZ, Alvaro, one of the numerous band of Portuguese explorers who, in the earlier part of the 15th century, took part in the search for a sea-passage into the Indian Ocean, was born about the year 1420, and seems to have been brought up as page or esquire to Prince Enrique of Portugal. He was related to Joam Gonsalvez, discoverer of Madeira and governor of Funchal. While still a comparatively young man, he was commissioned to prosecute the exploration of the African coast. After visiting the mouth of the Senegal and landing on the island of Gorée, he succeeded in reaching Cape de Matos or Mastos, the most southerly point that had ever been attained (1446). Soon afterwards he took command of a second expedition, in which the utmost limit reached was Rio Tabite, a little to the south of Rio Grande. Ill health thereafter compelled his return to Portugal, where he was welcomed at court as a distinguished discoverer. Sea Azurara, Historia de la Conquista de Guine, and Joam de Barros, Asia, dec. i. lib. i. c. 13, 14....
FERNANDEZ, Diego, a Spanish adventurer and historian of the 16th century. He was originally educated for the church, but about 1545 he embarked for Peru, where he served in the royal army under Alonzo de Alvarado. Mendosa, marquis of Canete, who succeeded Alvarado as viceroy, bestowed on Fernandez the office of chronicler of Peru; and in this capacity he wrote a narrative of the insurrection of Giron, of the rebellion of Gonzalo Pizarro, and of the administration of Gasca. The whole work, under the title Historia del Peru, was published at Seville in 1571. It is written in a clear and intelligible style, and with more art than is usual in the compositions of the time. It gives copious details, and, as he had access to the correspondence and official documents of the royalist leaders, it is, although necessarily possessing a royalist bias, the fullest and most authentic record existing of the events it relates. A notice of the work will be found in Prescott’s History of the Conquest of Peru.
FERNANDEZ, Joam, a Portuguese traveller, also of the 15th century. Early in life he had been taken captive by pirates of Barbary. While amongst them he acquired a knowledge of Arabic, and had his curiosity stimulated with regard to the geography of the African continent. On regaining his freedom he joined an exploring expedition, and got himself landed at the mouth'pf the Ouro river (lat 23°N.), where, exposed to considerable hardship and danger, he spent seven months of a nomadic life with some of the native tribes, and acquired a considerable amount of information about the geography of the interior (1445). Two years afterwards he explored the territory in the neighbourhood of Cape Blanco. He deserves some notice as having been the earliest of modern African explorers. The narrative of his adventures, which is said by those who have seen it to resemble that of Mungo Park, is to be found in Azurara’s Conquista de Guine.
FERNANDEZ, Juan, a Spanish navigator and discoverer. While navigating the coasts of South America it occurred to him that the south winds thatalm03t constantly prevailed near the shore, and retarded the voyages between Peru and Chili, might not exist further out at sea. His idea proved to be correct, and by the help of the trade winds and some currents at a distance from the coast he made a voyage with so great rapidity that he was apprehended on a charge of sorcery. His inquisitors, however, accepted, with a readiness far from common, his natural explanation of the seeming marvel, and he was set at liberty. During one of his voyages in 1563 Fernandez discovered the two islands which now bear his name, He was so enchanted with their beauty and fertility that he solicited the concession of them from the Spanish Government. It was granted in 1572, but a colony which he endeavoured to establish at the largest of them soon broke up, leaving ι behind them a number of goats, the progeny of which still continue on the islands. In 1574 Fernandez discovered the islands of St Felix and St Ambrose, and his companions who survived him affirmed that during a voyage in 1576 in the southern ocean he came in sight of a continent, which must have been either Australia or New Zealand if the discovery is to be accepted as a fact, but more probably it was either a delusion or an invention of his followers. See Alexander Dalrymple, An Historical Collection of the several Voyages and Discoveries in the South Pacific Ocean, London, 1769-71.
FERNANDEZ, Juan, a Spanish sailor and adventurer. In 1531 he joined the army of the celebrated^ Francesco Pizarro, conqueror of Peru, with a small force, but in 1533 he passed into the service of his rival Pedro de Alvarado. When the latter, however, agreed for a sum of money to cede his claims on Peru and make over his navy to Pizarro and Almagro, Fernandez necessarily returned to the service of Pizarro, who not only granted him pardon, but gave him the command of the ship. In 1538 ho accompanied Antonio de Sedeno on an expedition despatched by the Spanish Government against the island of Trinidad. Instead, however, of attempting to fulfil the purpose of the expedition, they were tempted by rumours of the existence of gold to disembark on the mainland, where, after enduring great privations and hardships, both leaders died in the winter after they set out, without finding the object of their quest. The survivors, under four different^ leaders, and decimated by hunger, fatigue, and continual combats with the natives, managed to find their way to the Spanish settlements.
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FERNANDO DE NORONHA, a group of islands in the South Atlantic, about 194 miles N.E. of Cape St Roque, South America, 3° 50' S. lat., 32’ 25' W. long. The largest of them is about 20 miles in circumference, its surface is rugged, and it contains a number of rocky hills from 500 to 700 feet hjgh, and a mountainous peak towering to the height of about 1000 feet. The island is covered with wood, but on account of the irregular occurrence of rain, it contains scarcely any other vegetation. It has several har-hours defended by forts, and serves as a place of banishment for criminals from Brazil. The next largest island of the group is about a mile in circumference, and the others are small barren rocks. The convict village numbers about 1000 inhabitants, and consists of a square formed by the governor’s residence, a chapel, the prison, workshop, and Government stores, and three or four streets radiating upwards, and composed of wattle-built huts. About 1000 additional convicts are employed in cultivating the plantations in different parts of the island. The island is.occupied by about 150 soldiers and 6 officers under a governor. ►Stores, convicts, and mails are carried by steamer twice a month to and from Pernambuco.
See “Visit to Fernando Noronha” by Alexander Rattray, M.D., R.N., in Journal of the Royal Geographical Society for 1872.
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FERNANDO PO, or Fernao do Pao, an island on the W. coast of Africa, lying in the Bight of Biafra, about 20 miles from the mainland, in 3° 12' N. lat. and 3° 48' E. long. It is about 44 miles in length from N.N.E. to S.S. W., and about 20 in breadth. The coasts are steep and rocky, and the interior is mountainous. A ridge of mountains towards the centre of the island rises to the height of 8000 feet, and is terminated at each extremity by a peaked mountain,—the northern one (Ste Isabelle)attaining a height of 10,700 feet. The southern extremity of the island is also intersected by several steep mountains, varying from 1000 to 3000 feet. These mountains are covered, most of them to their summits, as are the intervening valleys, with dense forests of shrubs and lofty trees of luxuriant growth. The rocks are of volcanic origin; and the soil is rich and fertile, producing rice, sugar-cane, cotton, tobacco, yams, and palms. Antelopes, monkeys, sheep, goats, fowls, turtle, and fish are abundant. The climate is salubrious, though the rainy season lasts from May to December, and is succeeded by a season of dense fogs. The principal harbour, Port Clarence on the northern shore, is frequented by English vessels, especially for palm-oil. This island was discovered in 1471 by a Portuguese navigator, whose name it bears. It was taken possession of by Spain in 1778, but was abandoned in 1782. The English formed a settlement on the island in 1827, and made use of it as a harbour for the ships of war sent to watch the slave traffic, but they relinquished it in 1834; the Spaniards resumed possession of it in 1844, and changed its name to Puerto de Isabel. The population is about 15,000, and is composed partly of half-breed Protuguese, negroes formerly freed by the British, a few ...Europeans, and the native inhabitants called Edeeyahs or Bobies, who are in the proportion of ten to one of all the others, and whose jealous hostil ity perhaps, as much as the reputed insalubrity of the climate, has prevented the colonization of the island by Europeans. The Baptist missionaries who settled on the island during its occupation by the British were expelled by the Spaniards in 1858. See Benedetti, “Les îles espagnoles du golfe de Guinée,” in Bull. de la Soc. de Geogr., 1869.
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FERNEL, Jean François (1497-1558), a distinguished French physician, was born at Clermont in 1497. After receiving his early education at his native town, he entered the college of Sainte-Barbe, Paris, where he so distinguished himself in mathematics, philosophy, and languages, that not long after obtaining his M.A. degree he was offered a professorship in the college. This offer he, however, declined, choosing in preference to become a physician. He received his doctor’s degree in 1530, and was named professor of medicine in 1534. His extraordinary general erudition, and the skill and success with which he sought to revive the study of the old Greek physicians, gained for him a great reputation, and ultimately the office of physician to the court. He practised with very great success, and at his death in 1558 left behind him an immense fortune.
His principal works are Moηαlosphwrium, sire Astrolabii genus, generalis Horarii Structura et Usus; De Abditis Rerum Causis; Medicina ad Henrieum IL; and Consiliorum Medicinalium Liber. All of them have been several times reprinted.
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FERNOW, Karl Ludwig (1763-1808), German artcritic and archaeologist, was born in Pomerania, November 19, 1763. His father was a servant in the household of the lord of Blumenhagen. At the age of twelve he became clerk to a notary, and was afterwards apprenticed to a druggist. While serving his time he had the misfortune accidentally to shoot a young man who came to visit him; and although through the intercession of his master he escaped prosecution, the untoward event weighed heavily on his mind, and led him at the close of his apprenticeship to quit his native place. He obtained a situation at Lübeck, where he had leisure to cultivate his natural taste for drawing and poetry. Having formed an acquaintance with the painter Carstens, whose influence was an important stimulus and help to him, he renounced his trade of druggist, and set up as portrait-painter and drawing-master. At Ludwigslust he fell in love with a young girl, and followed her to Weimar; but failing in his suit, he went next to Jena. There he was introduced to Professor Reinhold, and in his house met the Danish poet Baggesen. The latter invited him to accompany him to Switzerland and Italy, a proposal which he eagerly accepted (1794) for the sake of the opportunity of furthering his studies in the fine arts. On Baggesen’s return to Denmark, Fernow, assisted by some of his friends, visited Rome and made some stay there. He now renewed his intercourse with Carstens, who had settled at Rome, and applied himself to the study of the history and theory of the fine arts and of the Italian language and literature. Making rapid progress, he was soon qualified to give a course of lectures on archaeology, which was attended by the principal artists then at Rome. Having married a Roman lady, he returned in 1802 ...to Germany, and was appointed in the following year professor extraordinary of Italian literature at Jena. In 1804 he accepted the post of librarian to Amelia, duchess-dowager of Weimar, which gave him the leisure he desired for the purpose of turning to account the literary and archaeological researches in which he had engaged at Rome. His most valuable work, the Kornische Studien, appeared in 3 vols., 1806-1808. Among his other works are— Das Leben des Künstlers Carstens (1806), Ariostos Lebenslauf (1809), and Francesco Petrarca (1818). Fernow died at Weimar, December 4, 1808. A memoir of his life by Johanna Schopenhauer, mother of the philosopher, Arthur Schopenhauer, appeared in 1810, and a complete edition of his works in 1829.
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FERNS, a large group of cryptogamie plants forming in a wide sense a very naturally limited group. In the article Biology (vol. iii. p. 694) it has been shown that the subkingdom Cormophyta includes three well-marked series, Bryoρhyta, Pteridoρhyta, Phanerogamoe. Of the second of these, Fems, in the most restricted acceptation of the word, are the most conspicuous representatives. It will be convenient, however, to give some account under the present head, not merely of ferns proper, but also of the other smaller groups, closely related to ferns and often spoken of in familiar language as Fern-allies, which are included in the Pteridoρhyta.
The life-history of all these is divisible into two distinct stages or generations, in which not only are the external morphological characters extremely different, but the physiological functions are also sharply contrasted. These stages have been termed in the article already referred to the sporophore and the oophore.
The vigorous vegetative forms which are what are familiarly understood when fems are spoken of are only one phase of their complete life-cycle. They are the sporophores; and the reproductive bodies they bear (spores) germinate without any process of fertilization, and are therefore not to be compared with seeds. The same thing is equally true of the other members of the series Pteridophyta, viz., horse tails, club mosses, selaginellas, &c....
A spore on germination produces a structure which, compared with its immediate parent, is relatively very small, and bears no resemblance to it in form or texture. It is called the prothallium; it is green and membranous, and attached to the surface of the ground by root hairs in ferns and horse tails; in adder's tongues and club mosses it is tuberous and subterranean, while in Rhizοcarpece and Selaginella it always remains more or less included within the cavity of the parent spore. The function of the prothallium is entirely reproductive; it develops sexual organs of two kinds, archegonia and antheridia, either upon the same or different prothallia. Hence, in contradistinction to the sporophore—the function of which in this group of plants is purely vegetative—the prothallial generation is termed the oophore.
History.— The older botanists, starting from the study of flowering plants, endeavoured to recognize in all other cases the same characteristic points of structure. They did not doubt therefore, arguing from analogy, that ferns were provided with true seeds. Gerarde (1597), remarking theappearance of young plants of NephroHum dilatatum in the neighbourhood of old ones, attributed this to the dissemination of seeds, “for I believe all plants have seeds in themselves to produce their kindes.” No one, however, at this time could say anything definite about the “seeds” of ferns, and they came to be regarded as highly mysterious. It was supposed that they were of an invisible sort, and by a transference of properties it came to be believed that the possessor of fern seed would be invisible too. Shakespeare makes Chamberlaine say, “We have the receit of fern-seed, we walke invisible.” Ray ridicules Tragus for spreading linen clothe upon the ground to catch the seed of ferns on the eve of midsummer night, when, as Ray properly observed, it would be indeed astonishing if any fell, seeing that it is not mature till the autumn.
Columna in 1648 compared the fern frond to butcher’s broom, and identified the fructification in the one case with the flowers in the other. Caesius came to his help, and, having examined the sori of a polypody, “telescopii adjumento,” detected what he supposed to be seeds, but which were probably only the spore cases. W. Cole appears to have been the first to microscopically observe the spores themselves (1669), and Ray himself described the hygroscopic movements of the spore-cases which assist the dispersion of the spores. Morison (1715) seems to have been the first to put the matter to the test of actual experience. He sowed the spores of hart’s tongue, and in due course, without, however, distinguishing clearly the two stages, raised plants from them. This important observation fell completely into oblivion, and when in 1789 Dr Lindsay, a Scotch physician settled in Jamaica, responded to a request of Sir Joseph Banks for fern plants from that island by suggesting that spores would be much more convenient to send, the latter was quite unprepared for the suggestion, which he treated as a great discovery. Dr Lindsay accordingly wrote a paper on the subject (which was published in the Linnean Transactions a few years afterwards), in which he figured the prothallial stages of Polypodium lycopodioides. The spores of ferns were still, however, regarded as equivalent to seeds, t.c., as the result of a process of fertilization similar to that which precedes the development of seeds in flowering plants. A variety of attempts were made to see in hairs or glands upon the young fronds, &c., something that would do duty for an anther. As late as 1832 De Candolle maintained the analogy of the prothallium to a cotyledon. In 1844 Nägeli discovered the antherozoids, motile bodies which are set free from the antheridium, and which perform in fems the function of pollen grains. All previous observers had tried to find fertilizing bodies on the vegetative generation, the sporophore, which produces only spores. In 1844 the final step was reached when Suminski found upon the prothallia the archegonia, flaskshaped bodies containing a central cell (oosphere) which, when fertilized by the antherozoids, develops into a sporebearing plant similar to that from which the cycle started. In 1850 Mettenius discovered the details of the reproduction in Isoetes. Since that time the researches upon the Pteridophyta have been very numerous, and are to be found quoted in Sachs’s Lehrbuch.
The whole group of the Pteridophyta may be classified as follows :—
Pteridophyta. —Conuophyta with two distinct stages in the life-cycle. Sporophore with high vegetative differentiation. Oophore inconspicuous and destitute of vascular tissue.
Class I. Filicince.— Leaves highly developed. Sporangia numerous on the fertile leaves.
Sub-Class 1. Filices. — Leaves without stipular appendages. Sporangia epidermal, containing spores of one kind developed in each from a single primary mother-cell.
Sub-Class 2. Stipulate:.— Leaves with stipule-like appendages. Sporangia containing spores of one kind developed in each from many endogenous primary mother-cells.
Sub-Class 3. Rhiaocarpeoe. — Spores of two kinds.
Class IL Equisetinae. — Leaves rudimentary. Sporangia 5-10 on the fertile leaves.
Class III. Lycopodinae. — Leaves small (except Isoetes'}, simple. Sporangia solitary.
Sub-Class 1. Lycopodiaceae. — Spores of one kind.
Sub-Class 2. Ligulatae. — Spores of two kinds.
I. Filicinae. —1. The Filices or ferns proper deserve consideration at greater length, both on account of their numerical preponderance over the other groups, and the popular favour which deservedly attaches to their great beauty and variety of form.
Commencing with the vegetative generation or sporophore, the following remarks briefly touch upon the most essential points in their organization.
In general habit, although with a certain characteristic appearance which, to the experienced eye, is an almost unfailing distinctive character, ferns are as various in stature and aspect as flowering plants. One genus, Cerαtopteris, is remarkable for its aquatic habit. The terrestrial forms vary from the Hymenophyllaceae, which have the small size and delicate texture of mosses, to the larger forms vzhich attain the size of shrubs, while some belonging to the tropics and the southern hemisphere havo a palm-like habit, and are called tree-ferns. Cyathea medullaris reaches 80 feet in New Zealand, and Alsophila australis even greater heights in Australia. The stem creeps on or beneath the surface of the ground as in the common bracken, or climbs up rocks and the trunks of trees {Davalliα canariensis). In the latter case it is usually densely coated with imbricated membranous scales. In stems of this type the internodes or spaces between the insertion of successive leaves (fronds) is considerable, and the growing point is often far in advance of the youngest frond. In a large number of herbaceous ferns, of which the common male and lady fems are good examples, the stem is short and erect or slightly inclined (fig. 1). The fronds are developed spirally, and in close contiguity without obvious internodes; they form, viewed from above, a large rosette with the growing point in the centre. Between the ordinary herbaceous ferns with short erect stems and the tree-ferns there is no hard and sharp line of demarcation. Most of the ferns of decidedly arborescent habit belong to the sub-order Cyatheaceae, which has a sporangium and receptacle a little different from that of the typical Polypodiaceae, but in many of the genera of Poly podiaceae, especially Dicksonia, there are species that assume a more or less decidedly arborescent habit Nearly all Filices are perennial, but we have an instance of annual duration in Gymnogramme leptophylla. Growing Point.— The apex of the stem, whatever the dimensions of the mature plant, is always occupied by a single apical cell, and the whole growth is entirely dependent upon the repeated segmentation of this cell. In form it is either wedge-shaped with a transverse section like that of a bi-convex lens, or it has the form of a three-sided pyramid with a convex base forming the outer face. In the former case the segments are produced from the cell alternately right and left, and the stem, which is gradually built up by the repeated subdivision of the segments so formed, is always distinctly bilateral, and produces its fronds in two rectilinear series. In the latter case the segments are derived in spiral succession from the three interior faces of the apical cell, and the leaves, which are developed from the masses of tissue to which these segments give rise, are gradually displaced from the simple triseriate arrangement due to the segmentation of the apical cell into more complicated forms of phyllotaxis.
Branching is effected by the partition of the growing point; the single stem therefore bifurcates. This scarcely ever happens in ferns with erect stems, such as Nephrodium Filix-mas, or in tree-ferns. New shoots are, however, sometimes formed from the bases of the leaf-stalks, just as in some species they are normally produced from the fronds themselves. When the terminal point is injured, lateral shoots are often formed in this way. A specimen of Dick sonia antarctica has been described with as many as twenty-nine crowns, due doubtless to such a cause.
Structure of the Stem. — The repeated subdivision of the cells of the growing point gives rise to a mass of tissue, at first uniform in character, but which is subsequently differentiated. Particular tracts of cells are modified in the process of growth to form the fibro-vascular bundles. These are more or less flattened plates irregularly elliptical in transverse section. As in all the Pterιdophyta they are closed, and incapable, when once formed, of further increase in diameter. They consist of a mass of “xylem” surrounded by “phloem.” The xylem consiste, in addition to a few spiral vessels at the foci of the elliptical tranverse section, of scalariform vessels—cells of comparatively large diameter, with oblique ends, and with their walls intermittently thickened by transverse projecting ridges (fig. 2). Amongst the vessels are oblong cells containing starch in winter (woodparenchyma). The phloem contains sieve-tubes, and external to these thick-walled bast fibres. The whole fibro-vascular bundle is bounded first by one or two layers of oblong starch-containing cells (phloem-sheath), and external to these by a single layer of narrower cells, often thickened externally and darker in colour—the vascular bundle sheath. In very slender stems the fibro-vasculαr bundles form a central axis tflymenophyllaceae), but when the stems attain any size they are arranged in an anastomosing cylindrical network (fig. 3), in which a mesh corresponds to the base of a frond. This cylinderseparates the remaining or fundamental tissues of the stem into two portions, an internal central medulla and an externaΓcortex. This is shown in fig. 4; the dark lines, however, do not belong to the bundles which correspond to the light spaces enclosed by them; the dark lines themselves consist of a mass of thickened elongated cells termed “sclerenchyma,” which form protecting sheaths to the fascicular tissue. The medulla and cortex are in the main formed of parenchymatous tissue, often loaded with starch. In Cyathea medullaris this starchy pith was used by the Maoris as an article of food. The medulla is not, however, entirely parenchymatous; it is usually permeated by a number of anastomosing filiform bundles (usually also invested with a sclerenchymatous sheath), which eventually pass into the leaves through the meshes in the fibro-vascular cylinder. The greater part of the fibro-vascular tissue of the leaves is, however, continuous with the lower portion of the margins of the meshes, which runs out into bundles arranged round the outer circumference of the leaf stalk, and surrounding therefore the bundles which pass through the meshes from the medulla of the stem. In some cases, however, these medullary bundles contract an adhesion to the margins of the meshes as they pass through them. The surface of the stem, and also of the leaf-stalks,
13 usually strengthened by the sclerenchymatous development of the superficial portions of the fundamental tissue. This coats the surface with a layer which would be impervious to air were it not interrupted by spaces filled with soft parenchyma, by which the internal tissues of the stem are brought into relation with the atmosphere. In Pteris aquilina, the rhizome or horizontal subterranean stem is marked laterally by two lines where the colourless cortical parenchyma is not covered in, and. in many tree-ferns the bases of the petioles have their sclerenchymatous investment perforated by pits filled in the living plant by a soft-celled tissue which speedily becomes pulverulent.
The roots of ferns are always slender and wiry. They are continually formed during the growth of the stem in acropetal succession. In tree-ferns they consequently accumulate on the lower portion as they grow downward, giving it a large apparent diameter. In creeping species they at once attach themselves. They are cylindrical in all cases, scarcely exceeding one-eighth of an inch in diameter, dark-brown approaching black in colour, and clothed with root-hairs.
In ferns the occurrence of a special form of “trichomes” is noticeable in the flat multicellular membranous scales, to which the name of “paleae” is given. They are found in the greatest abundance on the stem and lower part of the stipes, but they often extend to the rachides of the frond, and sometimes to the foliar surfaces, especially in young fronds. There is no definite correlation in the character of these paleae with other points of structure. The most characteristic are the long thread-like bright-brown paleae of EiLdicksonia, which are so abundant that those of Dicksonia Culcita are exported in quantity from Madeira to stuff cushions and mattresses; and the clathrate flat paleae, dull brown in colour and permeated by a distinct lattice-work of thicker cells, which occur in Vittama, Antroρhyum, and some species of Asplénium. By their abundance, position, size, shape, and texture, the paleae often furnish great help in characterizing species.
Stipes. —Although generally distinguished by this special name, the stipes is simply the petiole of the leaf. It is very rare to find a fern in which the blade of the leaf does not possess a distinct stalk. In about two-thirds of the Filices, including not only those with erect, but many with creeping stems, the stipes is continuous with the stem, without any articulation at the point of junction; and when the old fronds die, they do not become disjointed, after the fashion of the leaves of a deciduous tree. In about one-third of the Filices, on the contrary, there is a distinct joint at the point of junction between the stipes and the stem, and when the fronds fade, they fall away from the stem spontaneously, leaving a clean scar. In the classification proposed by John Smith, the Polypodiaceae are subdivided by this character. The ferns in which the leaf-stalk is continuous with the stem, as in Asplénium, Nephrodium, and Pteris, he calls Desmobrya. Those in which the old fronds become disarticulated at the base, as in Oleαndra, Platycerium, and Polypodium vulgäre, he calls Eremobrya; and he states, as the result of his experience as curator for 40 years of the Kew collection, that the Desmobrya may be more easily reproduced from spores, but that the Eremobrya show greater tenacity of life, and that in the importation of ferns from abroad the Eremobrya generally arrive in good condition, whilst the Desmobrya, especially such as have slender stems, often perish in the journey.
Fronds.— Iu Filices we get a more varied range of leafform than in any other order in the vegetable kingdom, and some of the most beautiful and complicated types that exist. In size the fronds vary from under an inch, as in some of the minute Hymenophyllae, to a length and breadth of from ten to twenty feet in the great Cyatheas and Dicksonias. To take examples of the leading types from amongst familiar British species, we have simple fronds in Scolopendrium vulgare, simply pinnate fronds in Asplénium Trichomoenes aηdLomaria Spicant, bipinnate in Nephrodium montanum and Polypodium Phegopteris, tripinnate or tripinnatifid in Cystoptems fragilis and Polypodium Dryopteris, and tecorn^oandinAsplenuimAdiantum-nigrum and Pteris aquilina. The primary divisions of a compound frond are called pinnae, the secondary divisions pinnules. In a deltoid frond, as in Cystopteris montana or Pteris palmata, the pinnae grow regularly smaller from the lower to the upper, and the lower pinnae have the pinnules of the under side exaggerated. A decrescent frond, as in Nephrodiτιm conterminum or Asplénium Trichomanes, has the pinnae largest at the centre of the frond, and gradually smaller both towards its top and bottom. There is no regular relation between the frond and its fructification. Species with fronds similar in texture, cutting, and veining are often found, when the fructification is examined, to stand widely apart in systematic position. · The growth of the fronds is very slow. The whole of the fronds of a rosette of Nephrodium Filix-mas have been in course of formation two years before the lamina begins to unroll. The development is basifugal, and often the fronds continue growing at the top a long time after they are fully unfolded and producing fructification at the base. This may be seen iu Hymenophyllum sericeum and Gymnogramme elongata; iu Lygodium the leaf-stalk resembles a twining stem, growing for a long time. Iu many cases the fronds are of two kinds, developing from the first in a conspicuously different manner, one kind remaining permanently barren, and the other alone producing fructification. Wo have instances of this in Lomaria Spicant and Cryptogramme crispa, and dimorphism is shown still more conspicuously in Platycerium, in which the barren fronds are uncut and spread out flat over the surface on which the plant grows, and the fertile ones are much larger, and stand erect, and are forked, from which it takes its common name of elk’s-horn fern. There is another striking instance of dimorphism in the section Dryηaria of the genus Polypodium, in which the barren fronds are brown in colour, rigid in texture, small in size, and lobed like the leaf of the common oak, and the fertile ones are several feet long, with elongated segments like those of Polypodium vulgare. In some ferns the fronds have a habit of taking root at the tip, and thus producing new plants. This is well shown in the walking-leaf of North America {Scolopendrium rhizophyllum), and amongst tropical ferns in Asplénium rhizoplωrwn and Acrostichum flagelliferum. Some species develop copious adventitious buds, from which the plant may be reproduced, sometimes scattered over the surface of the frond, as in Asplénium viviparum and A. bulbiferum, sometimes in the axils of the pinnae, as in Asplénium proliferwm and Nephrodium cicutarium. Venation.— In the arrangement of the veins of the fronds of Filices there is an extraordinary amount of variety. The different types, and the extent to which they prevail, and the use that may be made in the systematic arrangement of fems of the characters they furnish, were carefully worked out by Presl and John Smith. The two principal leading types are veins that, after once branching, do not again unite, and veins that, on the contrary, after branching, join one another so as to inclose areolae like the meshes of a net. Ferns that exhibit the first plan are said to be free-veined; the other kind are said to have anastomosing venation. The free-veined ferns form far more than half of the order. In the whole frond or its ultimate divisions there may be a midrib alone, as in Monogramme graminea or Hymenoρhyllum tuηbridgense; or the veining may be simply pinnate, that is to say, a midrib - with a series of parallel simple branches on each side, as in Nephrodium patens or N. prolixum ; or there may be a regular midrib from the base to the top of the frond or segment, with the side-branches branched again, a very common type shown in Pteris aquilina and Nephrodium...
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