MUSriNA GROT^P. 25 



sixtli and following segments have each a ventral basal fusiform area 

 provided with tubercles; the anal area has two submedian tubercles 

 and three lobes each side of these; above them is a row of minute 

 granules, ending each side in a larger granulate tubercle; tlien^ ai-e 

 no tubercles outlining tlic stigmal area; the stigmal plates are sub- 

 triangular, about one and one-half times their diameter apart, black, 

 and each with three pale areas containing a sinuous or S-shaped slit, 

 but these slits are not near each other at the end as iu Musca, and 

 there is no apparent button. 



It commonly breeds in manure of various kinds, but also in decaying 

 matter, and is not often passed by people, but there is one record. 

 It is recorded that in ])arts of Africa Stomoxys attacks dogs so 

 viciously that tlic ears are often seen raw and bleeding from their 

 bites. 



Mesemhrhui and Dasyphora. 



Portchinski has described and ligin-ed the larva? of Mesemhrina and 

 Dasijpliora} Ilis figures show the posterior spiracles with tlie wind- 

 mg slits as in Musca, and in Mesemhrina he figures the smgle great 

 hook, so that these genera also belong in the Muscinse as here re- 

 stricted. Both genera have the posterior spiracular plates semi- 

 circular, but in Mesemhrina tliey are very famtly trilobed; in both 

 genera the plates are very close together. 



Glossina. 



The tsetse fly normally deposits a full grown larva, although 

 specimens in captivity have sometimes deposited partly grown larvae. 

 Tliis larva is short, subcylindrical, of a yellowish-white color, and at 

 the truncate posterior end are two large, rounded, black processes, 

 which have finely granulated surfaces. At the ventral base of each 

 of the segments 4 to 10 is a narrow, transverse, fusiform ridge. Aus- 

 ten, in his account (Brit. Med. Journ., 1904, pt. 2, p. 659) says lliat 

 "in the larger larvae tlic tips of the moutli liooks can be seen, sliglitly 

 protruding from the cephalic end. " It would tlierefore apj)ear 

 that they had two separate mouth-hooks, and not one as in Stomoxi/s 

 and Musca. If this be the case Glossina is not closelv related to 

 Stomojys. 



MUSCINA GROUP. 



The larva? of the Muscina grou}) arc in general irlated to tlie true 

 Muscida?, but difl^er at once in the simple, short, })ointed slits in the 

 posterior stigmal plates. The great hooks lie close together so that 

 they approach the azygos condition seen in Musca. Most of tlie 

 classifications keep Muscina in the true Muscidtp, but from the larval 

 standpoint it must be separated. 



»Hor. Ent. Soe. Ross., vol. 20, pp. 91, 118, 1891. 



