200 



PRINCIPLES OF PLANT-TERATOLOGY. 



similar outgrowths occurred along a portion of the main 

 lateral veins (fig. 55 b) ; in other leaves it was the midrib 

 only which exhibited the phenomenon, the " enation " 

 beginning almost at the leaf-apex and gradually 

 widening towards the base, where it formed, on either 

 side of the midrib by fusion with the leaf -margin, a 

 distinct pocket (fig. 55 ft). In Ficus glomerata similar 

 "enations" on two of the lateral veins have been seen. 



In a later chapter the remarkable enations from the 

 lower surface in Xanthosoma are referred to. 



b 



Fig. 55. — Polygonum cuspidatum. Laminar enations from lower 

 surface of leaf. 



The case cited by Buchenau of two tobacco-leaves 

 united by their lower surfaces, and a similar case seen 

 in the mango (Man g if era indica) in which the two 

 halves of the double leaf so formed are equal in size or 

 nearly so, come under this heading, for one of the two 

 leaves may be regarded as an enation from the other. 



An interesting transitional case between a laminar 

 " enation " consisting of an entire leaf (i. e. an " ena- 

 tion" equal in development to that of the leaf bearing 

 it) and the subsidiary ones of Polygonum and Ficus, has 

 been seen in Janusia gnaranitica in which the enation 



