240 PRACTICAL LESSONS IN SCIENCE. 



phous, nine in one set and one in the other; and very rarely the 

 stamens are distinct. This great family, containing 1 some 6,000 

 species growing in all parts of the world, is divided into three 

 subfamilies. 



The Papilionacese includes the pea, bean and peanut ; the lu- 

 pine and the clovers; the locust, rosewood and many other fine 

 trees; indigo, camwood and other dyes; the gums tragaeanth 

 and kino; the balsams of Peru and Tolu; and the plant that 

 yields the medicinal product, liquorice, and species that yield good 

 fiber, besides many species that are cultivated for ornament, 

 as the laburnum and wistaria. The name is derived from the 

 corolla, which is composed of five petals of such form and arrange- 

 ment as to resemble a butterfly. The petals of this corolla have 

 received special names. The upper and larger one, which is gener- 

 ally wrapped round the others in the bud, is called the banner ; 

 the two side petals are called the wings, and the two lower ones, 

 the blades of which usually stick together inclosing the stamens 

 and pistil, are called the keel. 



The Csesalpmiese includes the honey locust, coffee tree, and 

 judas tree of the United States, and many valuable timber trees 

 from the tropical regions, as well as many dye-woods, and others 

 that produce valuable gums and balsams. The members of this 

 group have a somewhat irregular corolla, with usually ten dis- 

 tinct stamens, and often twice pinnately compound leaves. 



The Mimosese have regular flowers, distinct stamens, and twice 

 pinnate leaves. The most important product from this group is 

 gum Arabic or acacia, and the different varieties of acacia fur- 

 nish very fine lumber highly prized for furniture, veneers, and 

 ornamental purposes generally. Some members of this group 

 are especially interesting on account of the movements executed 

 by their leaves, expanding in the light, closing in darkness, or 

 upon the slightest touch or jar, opening again in a few moments. 

 Mimosa pudica, is so prompt in its movements that it is called 

 the sensitive plant; numerous others are more or less sensitive. 

 As a whole the pulse family is interesting, important, and well 

 worthy of study. The common bean plant is a good specimen 



