Vol. xxix] KNTOMOUICK AI. xi'.ws. 263 



striking. Mr. Busck reported it from only one locality. Lion 

 Hill, and Mr. Jennings did not send it in at all." The same 

 writer, 2 in mentioning the abundance of this mosquito at a 

 later date (1913), states, "In lots of mosquitoes taken recently 

 and sent for determination by Mr. James Zetek, the entomol- 

 ogist of the Canal Zone, both Mansonia titillans and Aedeo- 

 inyia squamipennis appear in considerable proportion." 



That M. titillans has continued to multiply with consider- 

 able rapidity is plainly shown by the number of this species 

 found among the mosquitoes caught by hand in the habitations 

 of the Canal Zone. From February i, 1916, to January 31, 

 1917, out of a total catch of 391,019 mosquitoes, 251,332, or 

 more than 64 per cent., were of this species. 



The association of the larvae of M. titillans with the Pistia 

 plant was first discovered by Prof. H. W. B. Moore, 3 of 

 Georgetown, British Guiana, in 1910. Later, in 1915, he 4 

 succeeded in observing also the egg-laying habits of the adult 

 female. The habits and life history of this mosquito are more 

 peculiar and interesting than those of any other of the many 

 varieties of whose habits and life history we have any knowl- 

 edge.* 



The egg of this species is small and dark colored. One end 

 tapers into a slender elongation which equals about one-half 

 the length of the egg. This elongation gives the egg the gen- 

 eral appearance of a minute Indian club minus the hand- 

 grasp. Eggs freshly deposited by females confined in breeding 

 jars, which did not contain plant life, were pale white but 



2 Ihid. 



:; Moore, H. W. B. Found at last. The Daily Argosy Demerara, 

 Jan. 27, 1910. Quoted by Dyar and Knab in Entomological News, 

 Vol. 21, p. 259, 1910. 



4 Dyar and Knab. Eggs and Oviposition in Certain Species of 

 Mausonia. Insecutor Inscitiae Menstruus. Vol. IV, Xos. 4-6, p. 62, 

 1916. 



[*Comparison should, however, be made with the similar habits oi 

 the larva of Cnlc.r pfrtnrbans. See Smith, J. I'-., Hnt. News, xix, pp. 

 22-25, P' S - iii-iv, Jan.. 1908, and Grossbeck, J. A., /. c., pp. 

 pi. xxiii, Dec., 1908. En.J 



