170 RHAMNACE/E. 



circumscissile ; the putamen thick and bony, ovoid or len- 

 ticular, two - three-celled with a single erect seed in each 

 cell, or by abortion one-celled and one-seeded, indehiscent. 

 Seed not grooved, with a thin membranaceous testa. Al- 

 bumen wanting, or an extremely thin layer. Cotyledons 

 very large, thick and fleshy, plane (not involute) : radicle 

 small, inferior. 



Shrubs, with rigid and more or less spinescent branches, 

 alternate and nearly distichous triplinerved leaves, and small 

 axillary greenish flowers, in little cymes or umbellate fascicles 

 which seldom exceed the petiole. Stipules one or both spi- 

 nescent, or minute, and often caducous. 



Etymology. Said to come from Zizouf, the Arabic name. 



Geographical Distribution. A pretty large, chiefly subtropical genus, 

 belonging principally to the Old World, especially to the Mediterranean, 

 Arabian, and East Indian regions. A few have been detected in tropical 

 America, and one in Texas and on the northeastern borders of Mexico ; 

 namely, the Rhamnus obtusifolius, Hook., the flowers and fruit of which 

 have recently been obtained by Messrs. Lindheimer and Wright. 



Properties. The fruit in this genus is destitute of the purgative or 

 active qualities which generally prevail in the family ; that of several spe- 

 cies is esteemed as an article of food. The drupes of the Lote-bush (Z. 

 Lotus), which gave its name to the ancient Lotophagi, are still gathered 

 for food by the Arabs in Barbary. From Z. vulgaris and Z. Jujuba is ob- 

 tained the well-known gummy extract called jujube paste. Two Brazilian 

 species with edible fruit are known. That of the species here figured is 

 said by Dr. Gregg to be edible, but rather astringent. Its fruit is formed 

 in Texas the year after flowering, as noticed by Mr. Wright. 



PLATE 163. ZizYPHus obtusifolia (Rhamnus obtusifolius, Hook, in 

 Torr. cj- Gray, Fl. 1. j). 685*) ; from Texas, Lindheimer. 



1. A magnified flower, seen from above, showing the disk, &c. 



2. A petal and stamen, more magnified. 



3. Vertical section of the flower, magnified. 



4. Magnified section of a drupe (by abortion one-celled) and of the embryo. 



5. Transverse section of the same, showing the vestiges of the second cell. 



6. The embryo, magnified. 



* Also Paliurus Texanus, Jl. Scheele in LiniKEa, 21, p. 580 (1648). 



