GLOSSINA 



«43 



potcimi. According to Kinghorn, copulation in G. morsitans lasts 

 for several hours. The female in due course produces a single larva, 

 and may produce a second after fourteen to fifteen|days. At the 

 completion of intra-uterine lifejthe larva almost completely fills 

 the abdomen of the mother. Its extrusion takes place^very rapidly, 

 and it commences to crawl at once. The larvae, which are yellow- 



FiG. 435. — A Glossina in the Act of giving Birth to a Larva. 

 (Modified after Newstead.) 



a 



b 



coloured, are to be found as a rule near the roots of ban ana- trees. 

 These larvae are composed of twelve segments, the anterior of which 

 carries the two minute mouth-hooks, and the posterior a dark hood 

 or anal segment. The larvae retire to some hole, and in a few hours 

 become jet-black pupae, from which the fully developed insects 

 issue in about six weeks. 



The pupa is 5-53 (5 to 6) millimetres long, 

 and 3-2 (3 to 3-75) broad, according to an 

 average of twenty measurements by Kinghorn, 

 with twelve segments. The anterior four 

 show the longitudinal seam, which bifurcates 

 at the fourth segment, forming an opening 

 through which the imago escapes. The first 

 segment carries the mouth, and the twelfth 

 two lateral tumid, tuberculated lips, con- 

 nected by dorsal and ventral ridges enclosing 

 a pit, in which the posterior stigmata can be 

 seen. 



The larvae of G. palpalis measure 4-5 by 175 

 millimetres, and the pupae 5 to 5-75 by 3 

 millimetres. 



According to Kinghorn, forty-seven to 

 fifty-three days elapse from the birth of the 

 larva to the escape of the im^igomG .morsitans . 



Bionomics.— As G. palpalis is most prob - 

 ably the sole means of propagation of human 



trypanosomiasis, it is important to have some idea of what is 

 known as to its bionomics, which have been carefully studied by 

 Hodges and Bagshawe. 



The main resort of the fly is to be found in bush near water, 

 especially in the undergrowth composed of shrubs, bushes, vines, 



Fig. 436. — Pupa of 

 A Tsetse-Fly. 



(After Austen, from 

 ' Tsetse-Flies.') 



a, Magnified; b, 

 natural size. 



