MOSQUITOES IN GENERAL 



45 



Tlie question was finally set at rest by Macloskie (1887), 

 who succeeded in demonstrating' a poison gland in mos- 

 quitoes and in showing- that this poison gland is connected 

 by a duct Avith the mouth-parts. This venemo-salivary 

 duct is very fine, running backward in the lower part of 

 the head in the throat and terminating- in the prothorax 

 in glands of characteristic structure. The g-lands are in 

 two sets, each set consisting of three g-lands, two of which 



Fig. 3. — Section of head of Mosquito showing poison ghmd at p 

 enlarged. (Redrawn from Macloskie.) 



are ordinary salivary glands and the third (between the 

 other two) having a different appearance and structure 

 and secreting the poison. 



Miall, of England, as late as 1895 stated that it could 

 not positively be said whether poison is injected into tlie 

 wound or not. Overlooking, or not accepting-, Macloskie's 

 demonstration, he says : " No poison has hitherto been 

 demonstrated, and there is some reason to believe that the 



