JALAP, a cathartic drug consisting of the tuberous roots of Exogonium Purga, Benth., a convolvulaceous plant growing on the eastern declivities of the Mexican Andes at an elevation of 5000 to 8000 feet above the level of the sea, more especially about the neighbourhood of Chiconquiaco, and near San Salvador on the eastern slope of the Cofre de Perote. In these localities, where the temperature varies during the day from 60° to 75° Fahr. (15° to 24° C.), and rain falls almost every day, it flourishes in the deep rich soil of shady woods. Jalap has been known in Europe since the beginning of the 17th century, and derives its name from the city of Jalapa in Mexico, near which it grows, but its botanical source was not accurately determined until the year 1829, when Dr Coxe of Philadelphia published a description and coloured figure taken from living plants sent him two years previously from Mexico. The Jalap plant has slender herbaceous twining stems, with alternately-placed cordate acuminate leaves sharply pointed at the basal angles, and salver-shaped deep purplish-pink flowers. The underground stems are slender and creeping; their vertical roots enlarge and form turnip-shaped tubers, which, as they do not bear leaf organs on their surface, are sometimes called tubercules. The roots are dug up in Mexico throughout the year, and are suspended to dry in a net over the hearth of the Indians’ huts, and hence acquire a smoky odour. The large tubers are often gashed to cause them to dry more quickly. In appearance they vary from spindle-shaped to ovoid or globular, and in size from a pigeon’s egg to a man’s fist. Externally they are brown, and marked with small transverse paler scars, and internally they present a dirty white resinous or starchy fracture. The ...

JALAPA, or Xalapa, the Aztec Xalapan, a town of Mexico, in the state of Vera Cruz, and about 70 miles inland from the city and port of that name, with which it communicates by a railway opened since 1870. There are few towns in Mexico which are so happily situated: at a height of 4500 feet above the sea, on the edge of the plateau behind which towers the summit of Macultepec, it looks out over the rich lowlands of the tierra cαliente, enjoying their beauty and escaping their baneful vapours. The immediate vicinity is abundantly fertile, and yields a harvest of rare variety for the botanist. The town lost much of its importance as a commercial entrepot by the opening of the railway from Vera Cruz via Orizaba to Mexico, but the line above mentioned may help to restore its prosperity. Of chief note among the public buildings are the principal church and the old Franciscan monastery, built in 1555. The population is stated at 10,000.