VEINS AND RIBS OF LEAVES. 167 



and Boxburghia viridiflora, t. 57. The 

 greater clusters of vessels are generally 

 called nervi or costcs, nerves or ribs., and 

 the smaller vena, veins, whether they 

 are branched and reticulated, or simple 

 and parallel. 



Avenium, veinless, and e?ierve, ribless, are 

 opposed to the former. 



Trinerve, three-ribbed, is applied to a leaf 

 that has three ribs all distinct from the 

 very base, as well as unconnected with 

 the margin, in the manner of those 

 many-ribbed leaves just cited, as Blakea 

 trinervis*, Curt. Mag. t. 451. 



Basi trinerve, three-ribbed at the base, is 

 when the base is cut away close to the 

 lateral ribs, as in Burdock, Arctium 

 Lappa, Engl. Bot. t 1228, Tussilago, 

 t. 430 and 431, ar*d the great Annual 

 Sunflower, 



Triplinerve, triply-ribbed, when a pair of 

 large ribs branch off from the main one 

 above the base, which is the case in 



* Authors incorrectly use the termination trinprvius, 

 trinervia, &c. for the more classical trinervis, trinerve, 

 enervis, enerve. 



