178 RHAMNACEiE. 



at the base. Seed erect, filling the nucules (pyrenae), con- 

 vex (not at all grooved or excavated) on the back ; the char- 

 taceous or membranaceous testa somewhat adnate to the 

 putamen ; the raphe lateral, next to one marghi of the coty- 

 ledons. Embryo large, surrounded by a thin layer of fleshy 

 albumen : the broad cotyledons flat or plano-convex, usually 

 fleshy, not at all revolute, parallel with the axis: radicle 

 very short, inferior, turned a little from the hilum. 



Shrubs, or small trees, unarmed; with the deciduous or 

 sometimes coriaceous and persistent leaves alternate, petioled, 

 strongly pinnately veined ; the primary veins equal, parallel, 

 straight or a little curved, running obliquely and without 

 branching from the midrib to the margin. Stipules minute, 

 deciduous. Flowers all perfect, white, sometimes reddish, 

 clustered in axillary cymules or umbels. 



Etymology. Probably from frango, to break, in allusion to the brittle- 

 ness of the stems. 



Properties. The bark of F. vulgaris yields a yellow coloring matter, 

 and is purgative, acrid, and bitter. The drupes are more or less purgative. 



Geographical Distribution, Sic. This Tournefortian genus, which is 

 surely distinct from Rhamnus, as Mr. Bennett has remarked, belongs to the 

 northern temperate region ; three species are natives of Europe and North- 

 ern Asia ; one, of the Azores ; and one, F. Californica, with coriaceous 

 leaves and large dipyrenous fruit, of California, namely, Rhamnus Californi- 

 cus, Esch., and R. oleifolius. Hook., to which must be added, apparently as 

 varieties only, the R. laurifolius and R. leucodermis, Nutt., and even R. to- 

 mentellus, Benth. 



PLATE 167. Frangula Caroliniana : — a branchlet in flower. 



1. A flower magnified. 



2. A petal : 3. inside view of a stamen, more magnified. 



4. Vertical section of a flower, magnified. 



5. Pistil magnified, with the three-celled ovary transversely divided. 



6. A drupe, of the natural size. 



7. Transverse section of the same, magnified, showing the flat cotyledons. 



8. One of the cocci, seen from the inner side, more magnified. 



9. Vertical section of the same, and of the seed and embryo. 



10. A seed detached and magnified, showing the lateral raphe. 



11. Embryo detached entire, magnified. 



