CLASSIFICATION OF ANGIOSPERMS. 591 



Ricinus communis or Castor-Oil Plant is an annual licrlj in tiie 

 temperate regions but is shrub-like and perennial in tropical and 

 sub-tropical countries. In temperate regions the plant is from 

 I to 5 M. high ; the leaves are peltate and 6- to i i-palmately-lobed ; 

 the flowers are greenish, apetalous, monoecious and in racemes, 

 the pistillate being above the staminate on the flower-axis ; the 

 fruit is a 3-locular, oval, spinous capsule, which dehisces septi- 

 cidally (Fig. 237, B). The seeds are anatropous, somewhat flat- 

 tened-oblong ; 10 to 16 mm. long and 4 to 8 mm. in diameter; 

 smooth, mottled grayish-brown or yellowish-red, with a promi- 

 nent caruncle ; hard but brittle testa, thin white tegmen, large oily 

 endosperm, and thin foliaceous cotyledons at the center. The 

 seeds contain 45 to 50 per cent, of oil which constitutes the Castor 

 Oil of medicine and a large amount of proteins in the form of 

 aleurone grains (Fig. 250, D). The cake from which the oil is 

 expressed contains a poisonous principle known as ricin which 

 is apparently poisonous to cattle, but not to poultry. 



Croton Tiglium is a shrub or small tree indigenous to tropical 

 Asia and extensively cultivated in tropical countries ; the leaves 

 are alternate, oblong-lanceolate with petioles which are glandular 

 at the base, but wanting in the star-shaped hairs so characteristic 

 of other species of this genus ; the flowers are small, moinecious 

 and in terminal racemes, the pistillate being above and the stam- 

 inate below ; the fruit is a 3-locular, septicidally dehiscent capsule. 

 The seeds resemble those of Ricinus in size and structure, except 

 that they are less smooth, more brownish in color and the caruncle 

 is quite small. 



They contain a fixed oil which is obtained by expression and 

 which is poisonous and a powerful cathartic. The seeds of a 

 number of the other members of the Euphorbiace:e contain fixed 

 oils resembling those of Croton and Ricinus, as Cukcas, the seeds 

 of Jatropha Curcas of tropical America. Mexican Ckotux Oil 

 is obtained from the seeds of Euphorbia calyciilatn. The seeds of 

 the Caper Spurge or Wild Caper {Euphorbia Lathyris), nat- 

 uralized in the United States from Furope, also contain a fixed 

 oil resembling that of Croton. The seeds of Joauncsia Princcps 

 of the maritime provinces of Brazil are also powerful purgatives. 



M allot us philippinensis is a shrub or small tree found in trop- 



