MOSQUITOES IN GENERAL 13 



what heavier creosote oil was iDOured. This was jai- No. 2. 

 When at -4.15 r.M. the creosote was poured in jars 1 and 2, 

 no pupae were observed, but all larvse were full grown or 

 nearly so. After fifteen minutes ten pupje were observed 

 in jar 2 and five in jar 1. Ten minutes later fifteen were 

 counted in jar 2 and thirteen in jar 1. Twenty minutes 

 later there were nineteen in jar 2 and twenty -two in jar 

 1. Fifteen minutes later still there were nineteen in jar 2 

 and twenty-two in jar 1. Thirty minutes later there were 

 seventeen in jar 2 (two having- died in the interval) and 

 twenty-eig-ht in jar 1. As above stated, over nig-ht a num- 

 ber of adults issued, ten in jar 1 and eight in jar 2, and 

 twenty-four hours later ten more adults issued in jar 1. 

 It must be remarked that the full grown larvae struggled 

 violently on perceiving the uncomfortable presence of the 

 creosote, and as they were just ready to transform, this 

 violent struggling evidently assisted in the breaking of 

 the larval skin, leaving the pupa bare. This transforma- 

 tion from larva to pupa is hardly as interesting as the 

 rapid development of adults, eighteen of which issued 

 within fifteen hours after transformation to pupa, whereas 

 j)reviously the shortest duration of the pupal state which 

 we had observed was forty-eight hours. It looks like an 

 effort of nature to perpetuate the species in the presence 

 of a unique emergency. 



Mosquito Songs. 



Probably owing to an association of ideas, the curious 

 sound made by mosquitoes as they approach one's ear is 



