bush, banana-plantation, or even reeds " (Austen). It may be added 

 that the cover haunted by the majority of Tsetse-flies " is mainly 

 found in the valleys of rivers and watercourses and on the shores of 

 lakes " (Austen). 



The Classification of Tsetse- Flies. 



Two systems of classification have been proposed for the genus 

 Glossina that of Major E. E. Austen, of the British Museum (Natural 

 History), which is founded upon external characters ; and that of 

 Professor Robert Newstead, F.R.S., of the Liverpool School of Tropical 

 Medicine, based upon the morphological characters of the male genital 

 armature. 



Austen divides the genus into four groups, which, as originally 

 constituted, are as follows : The GLOSSINA PALPALIS Group, consisting 

 of G. palpalis, Rob.-Desv., G. caliginea, Austen, G. pallicera, Bigot, 

 and G. tachinoides, Westw. ; the GLOSSINA MORSITANS Group, com- 

 prising G. morsitans, Westw., G. pallidipes, Austen, and G. longipalpis, 

 Wied. ; the GLOSSINA FUSCA Group, formed by G. fusca, Walk., 

 G. fuscipleuris , Austen, G. nigrofusca, Newst., and G. tabaniformis , 

 Westw. ; and, lastly, the GLOSSINA BREVIPALPIS Group, the components 

 of which are G. brevipalpis, Newst., G. medicorum, Austen, and G 

 longipennis, Corti. 1 



In Newstead's scheme the genus Glossina is divided into only three 

 groups, the original arrangement being : The GLOSSINA FUSCA Group, 

 comprising G. fusca, Walk., G. nigrofusca, Newst., G. brevipalpis, 

 Newst., and G. longipennis, Corti ; the GLOSSINA PALPALIS Group, 

 composed of G. palpalis, Rob.-Desv., G. maculata, Newst., 2 G. caliginea, 

 Austen, G. tachinoides, Westw., G. fuscipes, Newst., 3 and G. pallicera, 

 Bigot ; and the GLOSSINA MORSITANS GROUP, which includes G. 

 morsitans, Westw., G. submorsitans, Newst., 4 G. pallidipes, Austen, 

 and G. longipalpis, Wied. 



For the distinctive features of these two classifications, into which 

 we cannot enter here, the reader is referred to Austen's " Handbook " 

 (3) and Newstead's able paper (105), both of which were published in 

 1911. 



In 1919 an account of the genital armature of female Tsetse-flies 

 was given by Miss A. M. Evans (51). The structures in question, 

 which had not previously been studied, were found to afford few 

 characters of definite specific value in the case of the G. palpalis and 

 G. morsitans Groups ; but in the remaining two divisions of the genus 

 the conditions met with confirmed the conclusions as to validity of 

 species already based upon other characters. 



1 This classification dates from 1911; during the eleven years that have 

 elapsed since its publication, five new species, G. austeni, Newst., G. ziemanni, 

 Griinb., which are additions to the Glossina palpalis Group ; G. severini, 

 Newst., G. schwetzi, Newst. & Evans, and G. haningtoni, Newst. & Evans, have 

 been described, while the name G. fuscipes, Newst., has been found to denote 

 simply the eastern race of G. palpalis. 



2 Not now regarded as a valid species. 



3 Now considered to be merely the eastern race of G. palpalis, Rob.-Desv. 

 (vide supra, Note J ). 



4 Held by Austen to be a f or m or race of G. morsitans, Westw. (vide infra, p. 15). 



