116 GNATS OR MOSQUITOES — CHAPTER VII 



are species in which both sexes suck animal blood (this is 

 said to be the case in an Egyptian species and in two 

 Italian ones ; it has also been observed in two species 

 found in Madagascar, and has been noticed at Bannu (N. 

 India)." 



When in the humour to attack, it is not only man, but 

 also other mammals as well as birds that are laid under 

 contribution ; and it is propable that they do not even con- 

 fine their attention to warm-blooded animals, for if, as is 

 most likely the case, they are the habitual intermediate 

 hosts for the majority of the class of protozoal blood-para- 

 sites, of which that of human malaria is the best known 

 example, it seems likely that tortoises and frogs are the 

 chosen victims of certain species, as haematozoa closely 

 allied to Laverans parasite are well known to occur in 

 animals of these classes. 



Bovine malaria has been shown by Smith and Kilborne 

 to be carried by a tick (Ripicephalus annulatiis) , but owing 

 to the amphibious habits of the former animals it is 

 unlikely that the alternative host of their malaria can be 

 any wingless arthropod. 



The staple food of the larvae of all the well-known genera 

 is undoubtedly of a vegetable character, such as monocellular 

 and filamentous algae, and in dissecting larvae I have never 

 met with anything else in the contents of their stomachs. 

 There can be no doubt, however, that they feed also on 

 animal matter, and may be not only predatory, but actually 

 cannibaHstic. The larvae of Corethra are said to be espe- 

 cially remarkable for procHvities of this sort, but I have no 

 personal experience of this genus, and otherwise there seems 

 but little difference in the habits of food of the different 

 genera. The Indian species of Anopheles are no exception 

 to this. Quoting from a communication to the Bombay 

 Natural History Society, advance proofs of which have been 

 kindly sent me by the author, Mr. E. H. Aitken, one of 

 our best field naturalists, I extract the following graphic 

 description of their habits : — 



"The favourite vegetable food is a soft /wcms, very like 

 cotton wool dyed green, which is found in clear running 



