CLASSIFICATION OF ANGIOSPERMS. 377 



HYSSOP (Gratiola ofHcinalis) of Europe contains gratiolin, a bitter 

 glucoside, and gratiosolin. The leaves of Curanga amara of the 

 East Indies contain a glucoside, curanjiin, which resembles digi- 

 talin in its action. 



h. BIGNONIACE^ OR TRUMPET-CREEPER FAM- 

 ILY. The plants are shrubs, trees or woody vines, and are repre- 

 sented in the United States by the catalpa tree (Catalpa bigiio- 

 nioidcs) and the trumpet creeper {Tccoina radicans). The bark, 

 pods and seeds of Catalpa have been used in medicine and con- 

 tain a bitter principle, catalpin, a glucoside and several crystalline 

 principles. The trumpet cre-Eper contains narcotic poisonous 

 principles. The leaflets of Carooa {Jacaranda Copaia), and other 

 species of Jacaranda contain the alkaloid carobine. an aromatic 

 resin, carobone and a principle having the odor of coumarin. 



i. PEDALIACE^. The plants are herbs indigenous to the 

 Tropics of the Old World, some of which are now cultivated in 

 the Tropics of both hemispheres. Benne oil (oil of sesame) is 

 obtained from the seeds of Sesamnm indicum by expression. It 

 consists chiefly of a glycerite of oleic acid, a glycerite of linoleic 

 acid, and myristin, palmitin and stearin. It is a bland, non-drying 

 oil and is used like olive oil. 



j. ACANTHACE.E OR ACANTHUS FAMILY. The 

 plants are mostly tropical perennial herbs, or shrubs with opposite 

 leaves, in the mesophyll or epidermal cells of which cystoliths 

 usually occur (Fig. 221). Several genera are represented in 

 the United States, one of which, Ruellia {Ruellia ciliosa), is the 

 source of the spurious spigelia which has been on the market for 

 some years past (p. 504). 



Ruellia ciliosa is a perennial herb which is distinguished from 

 the other species of the genus Ruellia by the leaves, stems and 

 calyx being distinctly pubescent. The leaves are ovate-lanceolate, 

 nearly sessile and entire ; the flowers are blue, sessile, solitary, or 

 two or three in a cluster, in the axils of the leaves ; the stamens are 

 4, and exserted. The fruit is an oblong, terete capsule containing 

 from 6 to 20 orbicular seeds. The plant is found from New 

 Jersey and Pennsylvania to Michigan and as far south as Florida 

 and Louisiana. Long cystoliths are found in some of the epi- 

 dermal cells of both surfaces of the leaf. 



