The genus Lathyrus, which contains the beautiful sweet pea of the garden, affords us several handsome wild species, but most of them are difficult of determination, and many of them are as yet much confused. This genus is quite closely related to Vicia, but, in general, the leaflets are broader, the flowers are larger, and the style is hairy down the inner side as well as at the tip.
Lathyrus vestitus is the common wild pea of the south. It is quite plentiful, and clambers over and under shrubs, hanging out its occasional clusters of rather large pale flowers.
L. Torreyi, Gray, found from Santa Clara County to Napa in dry woods, is a slender plant, having from one to three small white or pinkish flowers. It is remarkable for and easily distinguished by its very fragrant foliage.
WILD CUCUMBER. BIG-ROOT. CHILICOTHE.
Echinocystis fabacea, Naudin. Gourd Family.
Tendril-bearing vines, ten to thirty feet long. Root.—Enormous; woody. Leaves.—Palmately five- to seven-lobed; three to six inches broad. Flowers.—Yellowish white; monœcious. Calyx-tube.—Campanulate; teeth small or none. Corolla.—Five- to seven-lobed; three to six lines across. Staminate Flowers.—Five to twenty in racemes; their stamens two and a half, with short connate filaments and somewhat horizontal anthers. Pistillate Flowers.—Solitary; from the same axils as the racemes. Ovary.—Two- to four-celled. Fruit.—Two inches long; prickly. Syn.—Megarrhiza Californica, Torr. Hab.—Near the coast, from San Diego to Point Reyes.
The wild cucumber is one of our most graceful native vines. It drapes many an unsightly stump, or clambers up into shrubs, embowering them with its pretty foliage. Seeing its rather delicate ivy-like habit above ground, one would never dream that it came from a root as large as a man's body, buried deep in the earth. From this root, it has received two of its common names, "big-root" and "man-in-the-ground." Sometimes this may be seen upon the ocean beach or rolling about in the breakers, where it has been liberated by the wearing away of the cliffs. It is intensely bitter.
The seeds have a very interesting method of germinating. The two large radical leaves remain underground, sending up the terminal shoot only. They are so tender and succulent that they would be eaten forthwith, if they showed themselves above the ground. An oil expressed from the roasted seeds has been used by the Indians to promote the growth of the hair.
Authorities have differed about the classification of these plants, and they have been variously called Megarrhiza, Micrampelis, and Echinocystis, the latter being latest approved. We have several species. One common in the South is E. macrocarpa, Greene. This has a large oval, prickly ball, four inches or so long. When mature, this opens at the top, splitting into several segments, which gradually roll downward, like the petals of a beautiful white lily, showing their pure-white inner surfaces and leaving exposed the four cells in the center, with lacelike walls, in which nestle the large, handsome dark seeds. These seeds are often beautifully mottled and colored, and in the early days served the Spanish-Californian children for marbles.