ON THE DISTRIBUTION OF THE CULIClDyE 258 



tinguishing between them. It must be remembered that 

 besides these two there is a whole group of other species 

 as closely allied, but which are, nevertheless, universally 

 admitted as distinct. In cases of this sort, as in that of 

 An. superpictus and An. Bossii, it is probable that larval 

 characters, when we come to sufficiently know them, may 

 enable us to distinguish between species whose imagines may 

 be puzzlingly alike ; and when these have been thoroughly 

 examined, it is quite possible that the very variable C. 

 fatigans will have to be split up into several distinct types. 



