392 MEDICAL ENTOMOLOGY 



Nigeria ; it appears to attack travellers while in canoes, especially 

 during the month of May, in places where there is dense cover consisting 

 of long grass and water plants. Its early stages are unknown. 



Glossina tachinoides, Westwood. A darkish grey to brown species, 

 the smallest of all the tsetse flies. Thorax olive grey to smoke grey, 

 with longitudinal bands of the usual Glossina type. Abdomen ochra- 

 ceous buff with brown markings ; first segment with large circular 

 brown spots at the lateral angles, not reaching the lower border ; third 

 to fifth segments inclusive with dark lateral bands not reaching the 

 middle line or the lower borders, and leaving a buff longitudinal median 

 stripe. The size of the fly and the character of the abdominal markings 

 will enable the observer to distinguish it from all the other species of 

 Glossina. Length, according to Austen, male 6 to 6'75 mm. ; female 

 6'8 to 8'4 mm. 



The male genitalia are almost identical with those of palpalis, but can 

 be distinguished by the shape of the inferior claspers, the inner lateral 

 margins of which are proximally produced and broadly rounded ; the 

 outer margins are rounded at their distal extremities and deeply hol- 

 lowed out ; the inner margin is like a foot in shape, and has one or t\vo 

 hairs on it. 



According to Austen this species has a wide range in West Africa ; it 

 is also found in Senegal, the French Congo, The French Soudan, Ger- 

 man East Africa and Southern Arabia. It does not occur in the Congo 

 Free State, Uganda or the East African Protectorate. 



The habits of this species recall those of G. palpalis, though, accord- 

 ing to Roubaud, it prefers more open country, and groves along small 



streams ; in the rainy season it mav be found far from 

 Bionomics: early _ j-i r j T->I_JHJ 



any water. It readily feeds on man. Koubaud rinds 



SlclgGS* * 



that in captivity larvae are deposited on an average 

 every eight days, and that the pupal stage lasts from eight to thirty-five 

 days, the duration depending on the temperature. The larva and 

 puparium, according to Austen, have remarkably large and tumid anal 

 protuberances ; the stigmal cleft is similar in shape to that of morsitans, 

 but much wider than that of palpalis. 



Glossina maculata, Newstead. This species is represented at present 

 by a single specimen, a female, and is of doubtful validity; Austen regards 

 it as a specimen of palpalis, which has become spotted by some foreign 

 matter. Newstead,. on the contrary, has no doubt regarding its specific 

 identity, and refutes the statement that the dusky spots are due to 

 the. attentions of some other flies which were in .the same packet ! 



