varieties of £. Coca and the brochidodromous pattern typical of 

 E, novogranatense var. novogranatense. As will be discussed in 

 greater detail later, such extensive variation in leaf form and 

 venation can usually be explained ecologically, in relation to 

 differences in microhabitat experienced by individual leaves or 

 plants, but it is also an indication of the intermediate nature of 

 Trujillo coca between E. Coca var. Coca and £. novogranatense 

 var, novogranatense. 



Secondary veins of both varieties of £. Coca typically are 

 numerous (15-40 per leaf), closely spaced and of moderate 

 thickness. In both varieties of E. novogranatense, they are 

 usually fewer (8-18 per leaQ, more widely spaced and more 

 slender (Plate 39). Secondary vein divergence angles from the 

 midvein range between widely acute to perpendicular (80-90' 

 £. Coca vars., E. novogranatense var. truxillense) and narrowly 

 to widely acute (40-80^, £. novogranatense var. novograna- 

 tense, some specimens of E. novogranatense var. truxillense). 

 Secondary veins follow an initially straight, regular (£. Coca 

 vars.) or sinuous (£. novogranatense vars.) course, and gradu- 

 ally upcurve as they approach the leaf margins. The subsequent 

 branching behavior of these veins determines the basic con- 

 figuration of the overall venation pattern. These secondary veins 

 then either: (1) taper into a festooned system of high order, 

 intramarginal loops along the outer flanks of the superadjacent 

 secondary veins (eucamptodromous, £, Coca vars.) or (2) 

 recurve admedially (inward towards midvein) near the margin 

 and join these superadjacent secondaries at widely acute to 

 obtuse angles (80-100°) to form a series of (secondary) vein 

 arches (brochidodromous, £. novogranatense var. novograna- 

 tense). Secondary veins of £, Coca varieties and £. novo- 

 granatense var, truxillense normally are thicker, more prom- 

 inent and more numerous than in leaves of E, novogranatense 

 var. novogranatense. Secondary veins thus demarcate inter- 

 costal areas which are both more numerous and of greater 

 uniformity in size and shape in leaves of E. Coca varieties and E, 

 novogranatense var. truxillense than in most leaves of £. novo- 

 granatense var, novogranatense. Intersecondary veins of com- 

 posite origin are very few, but when present they are most 



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