174 RHAMNACE^. 



Fruit an oblong or ovoid drupe, with a thin sarcocarp, 

 or sometimes nearly juiceless ; the crustaceous putamen two- 

 celled. Seed solitary in each cell, oblong, erect, with a 

 membranaceous testa, not grooved ; the raphe lateral, or at 

 length dorsal. Eivibryo in the axis of fleshy albumen and of 

 about the same length : cotyledons narrowly oblong, flat 

 and thin, parallel with the dissepiment : radicle short, infe- 

 rior, slightly curved toward the axis. 



Shrubs erect, or often twining or climbing, with the alter- 

 nate leaves oval or oblong, entire or nearly so, strongly pin- 

 nately veined ; the veins numerous and nerve-like, approxi- 

 mate, oblique, straight and simple, connected by minute 

 transverse veinlets. Stipules subulate, minute. Flowers 

 small, greenish-white, perfect or somewhat polygamous, sol- 

 itary or cymulose in the axils of the upper leaves, and in 

 slender terminal panicles ; the drupes blackish or purple. 



Etymology. The name, which is not explained by Necker, is supposed 

 to commemorate some obscure botanist. 



Geographical Distribution. The genus, which is well marked in habit, 

 consists of one species indigenous to the Southern United Stales, a few in 

 subtropical North America, and several in tropical Asia. 



Properties. The fresh stems of our species are very lithe and tough ; 

 whence the popular name. 



Note. In B. volubilis we do not find the seed to be stipitate ; the em- 

 bryo is surrounded by a very distinct albumen ; and this is closely invested 

 by a thin and delicate testa, which is not adnate to the pericarp. 



PLATE 165. Berchemia volubilis, DC. ; — a branch in flower, of the 

 natural size. 



1 . Diagram of the aestivation and position of the parts of the flower. 



2. An expanded flower, magnified. 



3. A vertical section of a flower, magnified. 



4. Vertical section of a fertilized pistil, disk, &c., magnified. 



5. A stamen more magnified, seen from the outside. 



6. The same, seen from the inside. 



7. Fruit of the natural size. 



8. A magnified vertical section of a mature drupe, dividing both seeds. 



9. A transverse section of the same. 



10. The embryo detached, more magnified. 



