46 IXSECUTOR IXSCITI.E MENSTRUUS 



MOSQUITOES AT SAN DIEGO, CALIFORNIA 



By HARRISOX G. DYAR 



Under directions of Dr. L. O. Howard, of the Bureau of 

 Entomolog}-, U. S. Department of Agriculture, the writer spent 

 seven weeks in San Diego, Cahfornia, in the spring of 1916, 

 to determine whether A'cdes calopiis. the yellow fever mos- 

 quito, was present in that city. Exact observations were de- 

 sired, although general conditions indicated that the species 

 did not occur. These indications were borne out by the ex- 

 amination ; A'cdes calopiis was not found. 



In general it may be said that San Diego is not infested by 

 mosquitoes. Occasional single specimens of A'cdes sqiiamiger 

 may be found biting and one Ciiliseta incidens was taken hover- 

 ing suspiciously about the person ; Citlex coniitatus, also, may 

 be troublesome in unscreened houses ; a gorged female was 

 taken on the ceiling of a bedroom. But, in general, mos- 

 quitoes are seldom met with. The main residential part of 

 the city lies high and is continually swept by cold sea breezes, 

 conditions unfavorable for abundance of mosquitoes. The 

 following species were taken in the environs of the city. 



Culex tarsalis Coquillett. 



This species is not particular about its breeding places, the 

 larvae being found in all sorts of natural pools and even in 

 salt-marsh pools, where permanent. The larva are trans- 

 parent and colorless and develop very slowly. 



Culex stigmatosoma Dyar. 



This species breeds naturally in pools in stream-beds left 

 by high water, when these have become sufficiently stale, these 

 ])ools being without vegetation. Consequently, it takes readily 

 to artificial puddles, ponds and fountains. An egg-boat was 

 taken from the fish pond in the square in Old Town and bred 

 to maturity. An accidental pool on the grounds of the Theo- 

 sophical Homestead at Point Loma was stocked with larvae 

 of this species. 



