GLOSSINA MORSITANS 



397 



Neave states that this species is found in the type of country frequent- 

 ed by morsitans ; it is not entirely confined to the banks of rivers, but 

 is almost invariably associated with a large amount 



of bush, in low-lying river valleys. According to Bi o n ics and Early 



stages 



Neave it appears to have a seasonal prevalence in 



British South Africa, being most numerous during the wet season and 

 the following months. The opening up of the country, and its cultiva- 

 tion, seem to have a marked effect in reducing the numbers of pallidipes. 

 Very little is known regarding its early stages. Austen records the 

 main characteristics of the puparium, which measures from 6'4 to 7 mm. 

 The anal tubercles are separated by a wide U-shaped notch, not unlike 

 that of the puparium of fusca. 



Glossina longipalpis, Wiedemann. A large tsetse very closely resem- 

 bling pallidipes, but distinguished from it by the brown tips to the last 

 two joints of the front and middle tarsi, and the shape and structure of 

 the superior claspers of the male. The differences in the structure of 

 the external genitalia given by Newstead are as follows : 



Heel or posterior 

 lateral tooth. 



Single long hair on 

 distal margin. 



Inner flange-like ex- 

 tension of superior 

 clasper. 



Longest hairs of edi- 



G. longipalpalis. 



Outer lateral margin taking 

 same contour as the margin of 

 the clasper. 



Long and capable of over- 

 lapping corresponding hair on 

 opposite clasper. 



Greatest breadth about one- 

 fourth the width of the narrow- 

 est portion of the stem. 



Equal in length to the supe- 

 rior clasper. 



G. pallidipes. 



Outer lateral margin curved 

 inwards. 



Short and not capable of 

 overlapping hair on opposite 

 clasper. 



Breadth greater than the 

 width of the narrowest por- 

 tion of the stem- 



One-half the length of the 

 superior clasper. 



turn. 



Austen gives the distribution of this West African species as extend- 

 ing from Senegal to the Katanga District in the Congo Free State. 



Roubaud has studied the early stages of the fly, and finds that in 

 parts of Dahomey it may be seen in bush country, whereas in Central 



Dahomey it is met with in the vicinity of rivers and 



T , , j j , , , , Bionomics and Early 



streams. It is abundant during the rains, but almost stages 



disappears during the dry weather ; it chiefly feeds on 



game. In captivity the female deposits her larvae about every ten days ; 



the pupal stage lasts thirty-five days on the average. 



Glossina morsitans, Westwood. (Plate LI, fig. 2). "A medium-sized 

 light grey fly with a banded abdomen. Thorax light grey, with 



