occupied by stomata, averages 11.4%, and specimen means 

 range between 10-13% (Table 5). 



Epidermal papillae are either absent (e.g. Nazca#8), sparse or 

 prominent, but are consistently restricted to the lower epidermal 

 cells (Plate 37D, E, F). Papillae are always absent from both the 

 guard cells and their associated subsidiary cells of all stomata on 

 the lower leaf surface. 



crystals: Vein-associated prismatic or rhomboidal crystals of 

 calcium oxalate are typically very abundant and may occur also 

 in cells of either epidermal surface (Plate 38). 



FOLIAR SCLEREIDS: No foliar sclereids of any type were observed 

 in the archeological leaves examined. 



Recent Leaf Specimens 



LEAF FORM AND VENATION! Although Icavcs of the cultivated 

 cocas may exhibit similar and intergrading forms and patterns 

 of low and high order venation, a typological concept of leaf 

 form and venation can be formulated for them. The leaf 

 venation patterns which are considered "typical" for each of the 

 cultivated cocas are summarized in Table 4. These diagnoses are 

 based on observations of many more specimens than were 

 prepared for microscopic study (Table 2), and microscopic 

 examination was performed only on selected specimens which 

 represent the full range of variability within each variety. Leaves 

 of Amazonian coca {Erythroxylwn Coca var. Ipadu) are not 

 sufficiently distinct from those of £. Coca var. Coca in their leaf 

 venation to warrant separate description. It should be noted, 

 nevertheless, that particular leaf specimens may diverge from 

 this overall diagnosis in details of both low and high order 

 venation as well as in leaf form. 



Leaves are small to medium in size, ranging from 20-1 15 mm. 

 in length and 10-24 mm. in width. Leaves of Trujillo coca 

 typically are the smallest, whereas those of Amazonian coca 

 attain the largest sizes. All varieties of cultivated coca possess an 

 acute or cuneate leaf base. Leaf shape varies both within and 

 among varieties, but may be characterized as follows for each 

 variety: (1) f. Coca var. Coca, broadly lanceolate to elliptic, 



306 



