1906] 
KXAB—SU'ARMIXG OF CULEX PIPIEXS 
131 
Upon a recent trip to the west coast Dr. H. G. Dyar found a pair of CiiUseta 
consobrinii.t in copula, resting; on the under side of a hoard. This observation shows 
a wide departure from the short copulatorv act of Ciilc.r and Stegomyia. 
The crab-hole inhabitin'; Deinoceriies cancer swarms during the short twilight 
period just outside the crab-holes and copulation takes ])lace then. 
Goeldi has given a vivid account of the swarming of the common house-mos- 
qtiito of Para which he designates as Culex jatigans. Swarming takes place indoors 
when it is nearly or cpiite dark and there are separate swarms of males and of females. 
Such peculiar mating-habits surely indicate a distinct sjiecies. In the case of our 
Culex pipiens the males are never found in houses — unless, indeed, they hajjpen to 
come from larvae developed indoors. 
Mr. E. A. Schwarz has kindly placed at my disposal his observations made on 
a species of Culex, probably the Culex cuhensis of Bigot, at Cayamas in Cuba. The 
swarming occurred in the house, always on the side away from the sun, and when it 
was almost fully dark. The moscjuitoes could only be seen against the sky, when 
between the observer and the open doors and windows and close observation was 
impossible under the circumstances. However, the swarms in this case were made 
up of both se.xes anil copulation freely took place. A capture of 60 specimens from 
such a swarm contains 44 males and 16 females. 
In conclusion the curious reaction of a mosquito swarm to sound, related to 
Ostcn Sacken by a Cuban naturalist, seems worthy of notice. While a swarm of 
mosquitoes was hovering over the head of the observer a banil was playing at a dis- 
tance. IMienever the note A was struck the mosquitoes were all jirecipitated down- 
ward, striking against the face of the observer. A similar and quite independent 
observation is recorded by Howard. 
The bringing together of these notes shows how very meagre our knowledge of 
this interesting subject is and it is to be hoped that it will stimulate others to further 
observations. No claim of comjdeteness is made for the following bibliography. 
The works not seen by the writer are indicated with an *. 
