Plate 38. Archeological leaf specimens of Trujillo 

 coca (E. novogranatense var. truxillense). Photo- 

 micrographs of cleared leaves, taken with partially 

 polarized light. Crystals and lignified tissues (veins) 

 appear bright white due to their positive birefringence 

 in polarized light. Scale markers all = 100 yun 

 (micrometers). A. Midvein, secondary and high order 

 venation; note numerous crystals which appear as 

 white flecks along veins and in mesophyll. Specimen 

 "Nazca no. 8". B. Midvein with secondary vein, 

 tertiary vein and high order venation; note numerous 

 crystals as in Plate 38A, but mostly in mesophyll. 

 Cleared leaf specimen, Harvard Botanical Museum 

 accession no. 10-124. C. Midvein and diverging 

 secondary vein with many crystals. Cleared leaf 

 specimen "Nazca no. 4". D. Close-up of veinlet of 

 "Nazca no. 4, shown at lower magnification in Plate 

 38C, revealing crystals along veinlet. 



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