SUPPLEMENT. 



THE FAMILIES OF FLOWERING PLANTS. 



By Chaeles Louis Pollaed, 



CHAPTER XXI— Continued. 



We have now reached one of the largest, probably the most impor- 

 tant, and certainly one of the most distinct natural groups in the whole 

 vegetable kingdom; the group known for many years under the name 

 Leguminosae or Pulse Family, and still commonly so called. The 

 name is in allusion to the fruit, which consists of a single more or less 

 fleshy thin-walled carpel, bearing the seeds in one row. It is known 

 technically as a legume, and popularly as a pod, and is so characteris- 

 tic in appearance, that with very few exceptions an 3^ plant of this group 

 may be recognized, when in fruit, as a " leguminous " (legume-bearing) 

 plant. 



Eecent systematists, considering the remarkable differences in 

 floral structure that obtain among various subdivisions of the Legumi- 

 nosae, have treated the group as consisting of three families, and this 

 classificatiod is generally followed in America. These families are 

 known as the Mimosaceae, the Caesalpiniaceae, and the Papilionaceae. 



Family Mimosaceae. Sensitive-plant Family. Mimosa Family. A 

 group conspicuous in the tropics, very limited in the temperate, and 

 wholly absent from the arctic zones. It includes about 30 genera and 

 1400 species, the plants being herbs, shrubs or trees. They have alter- 

 nate leaves, which are nearly always pinnately compound after the pat- 

 tern of those in the common greenhouse sensitive plant {3Iimosa pudica). 

 The small perfect and quite regular flowers are borne in heads, spikes 

 or racemes. The calyx is cup-shaped, with from three to six teeth; the 

 corolla with a similar number of distinct or slightly united petals. The 

 stamens vary greatly in number in the different genera, some of them 

 being distinguishable from each other as genera only by the number of 

 stamens. The ovary is of course one-celled, and the fruit a legume, as 

 above explained. Fig. 116 conveys a good idea of the flowering branch 

 of an Acacia, which is a typical mimosaceous plant. 



Edible fruits are yielded by many tropical trees of this group, par- 

 ticularly by species of Inga and Prosopis. The latter is the well-known 



