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ON THE CHARACTERISTICS OF THE NEWLY DISCOVERED 

 TSETSE-FLY, GLOSSINA AUSTENI, NEWSTEAD; WITH 

 DESCRIPTIONS OF THE GENITAL ARMATURE OF GLOS- 

 SINA FUSCIPLEURIS, AUSTEN, AND GLOSSINA LONGI- 

 PENNIS, CORTI. 



By Pkofessor R. Newstbad, F.R.S., 



The Liverpool School oj Tropical Medicine. 



In pursuing my studies of the genital armature of the tsetse-flies, I have 

 been fortunate in securing some valuable and interesting material from various 

 parts of the African continent which has enabled me to offer a further con- 

 tribution on the specific characters of the recently discovered Glossina austeni, 

 Newst., from British East Africa ; to present a detailed account of the 

 armature of the apparently rare G. fuscipleuris, Aust., and to clear up some 

 doubtful points in regard to the structural details of the male genital armature 

 in G. longipennis, Corti. Later I hope to be able to offer some further remarks 

 on G. palpalis, R.D., especially in regard to the colour and structural variations 

 existing in this species. Meanwhile I may here state, for the guidance of the 

 student, that G. fuscipes, Newst., which was described by me as a distinct 

 species, must sink as a well-marked race of G. palpalis. 



Glossina austeni, Newst. 



G. austeni, Newstead, Ann. Trop. Med. and Parasit., vol. vi, no. IB., 

 pp. 129-130 (May 1912). 



The distinguishing characters of this insect are its small and slender form ; 

 the relatively narrow head ; the presence of a more or less clearly defined dark 

 bilateral stripe on the thorax ; the bright ochraceous or reddisli-ochraceous 

 abdomen, with its dark lateral markings, or interrupted bands ; the dark hind 

 tarsi ; and, in the male, the foot-like shape of the superior claspers (fig. 1, sc) and 

 the narrowly pointed, distal portion of the harpes (fig. 1, h). 



Though possessing dark hind tarsi this insect must undoubtedly be placed 

 in the " morsitans-growp " of the tsetse-flies, as the morphological characters of 

 the male genital armature show very clearly that it is related to the insects 

 comprised in this group. Of the species possessing dark hind tarsi the only 

 one with which G. austeni can possibly be confused is G. tachinoides. Both are 

 small and slenderly built insects, but the former may be distinguished at once 

 by its narrower front, especially in the male, and also, as already stated, by the 

 bright colour* of the abdomen and the presence of the dark lateral stripes on 

 the thorax. In the original description of G. austeni (I.e.) I stated that the 

 insect " bears a somewhat close resemblance to a dwarfed specimen of G. fuscaP 

 Now that I have a lono- series before me I feel that this statement cannot hold 



* Mr. Neave, who has seen examples of this insect in life, informs me that it is readily dis- 

 tinguished from all other tsetse-flies by its reddish colour. 



