related species, both wild and cultivated, are frequently mis- 
identified as FE. Coca. 
MATERIALS AND METHODS 
Mitotic counts were made from root tip meristems from 
greenhouse reared plants, pretreated in 0.004 M 8-hydroxy- 
quinoline at 15°C. for 3 hours (Tijo & Levan, 1950). Root tips 
were then rinsed in distilled water, stained 1/2 hour in 1% acetic 
orcein: | N HC1 (9:1) with gentle heating, and squashed in 45% 
acetic acid. 
Meiotic studies were conducted with flower buds fixed and 
stored in Carnoy’s solution (ethanol: acetic acid, 3:1). Tissue 
stored in Carnoy’s for up to 4 years provided adequately pre- 
served material for study. Microsporocytes were squashed and 
stained in acetocarmine. Photographs were taken with a Zeiss 
oil immersion lens under phase illumination. Herbarium 
vouchers are preserved at the Economic Herbarium of Oakes 
Ames (ECON). 
RESULTS AND DISCUSSION 
Chromosome numbers are summarized in Table Two. All 
counts showed 2n = 24 or n = 12, in agreement with earlier 
published counts for Erythroxylum. It would seem that n = 12 
is the base number for the genus. Some chromosomal ir- 
regularities, including chromosome bridges, were observed in 
microsporocytes of E. Coca (Plowman 6165, 6183). A more 
detailed investigation of additional material will be necessary 
for a better understanding of these features. So far as is known, 
all the species investigated here appear to be normal, sexual 
species. 
Cytological examination of preserved buds of Erythroxyvlum 
havanense Jacq.(Plowman & Davis 3563), E. Ulei O.E. Schulz 
(Plowman 6189) and E. areolatum L. (Kress s.n.) proved un- 
rewarding. The smallest buds (ca. 0.5 mm. diameter) showed 
pollen already formed. Furthermore, preserved material of 
these wild species was difficult to work with because of tissue 
hardness, preventing good squash-preparations. In the future, 
better results may be obtained by special pretreatment of buds 
or by examining root tips when material is available. 
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