Chromosomes of the tsetse fly, Glossina palpalis R.-D.

Mitotic metaphase chromosomes of the tsetse fly Glossina palpalis R.-D. have been investigated.The chromosomes studied were in circumoesophageal nervous tissue from young pupae, stained with aceto-orcein and spread by squashing.The diploid number of chromosomes was shown to be 6, consisting of 2 long pairs and 1 short pair at metaphase.This finding is discussed briefly in relation to previous descriptions of the chromosomes of G. tachinoides West. and G. morsitans morsitans West. and to accepted systematic divisions of the genus Glossina into subgeneric groups.I wish to thank Mr H. Dickson for assistance with photography. I thank Mr D. A. T. Baldry for advice and suggestions concerning the manuscript. Mr T. M. Leach has also made suggestions concerning the manuscript, and as Director of the Nigerian Institute for Trypanosomiasis Research, has given his permission to publish this paper.