36 MOSQUITO WiiKK IN KII AUTOUM, KTC. 



The sudd as Daiiii'ls' luis su^igL'stwl tliut liii'va' prutected 1)}' lli)atiiig sudd may l)i.' ciiri'icd 



mosquito loiig (listaiK't's, Hiid that new genera and species may in this way reach Egypt, 

 distribution rj^.j^^^^ j.|._.^ ^^.ij.|^ ^^f ^,^j^ liypothesis may well lie ti'iu'. hut as regards the second, 



I wiuil<l pniiir out thar little, if any, sudd tinds its way even su far north as 

 KhaiTuum. Floating islands of sudd are rarely encountered north of Dueim on 

 the Wliire Xik'. Thev get caught by the reedy ri\-cr banks and the low islands, 

 and ai'c ar all times liable to be broken up and dispersed by the jjaddle floats 

 of steamers. As a matter of fact, the distribution of mosiiuitoes indicated on the 

 map is, on the whole, an argument adverse to the ingenious theory of this able 

 obser\'er. 



' Laboratory Studies in Tropical Medicine, 1903 



