178 Mosquitoes 



held full-grown larvae, pupae, and emerging imagos. 

 The captured larvae devoured greedily the larvae of 

 a Culcx and C. consobrimis taken from the same pool. 

 The drain had been dry as a bone for more than a 

 month previous to this rain. Dr. Dupree watched 

 his captives, he says, with a view to determining their 

 manner of attacking their prey, and was unable to 

 confirm Dr. Howard's observation that they grasp it 

 just below the tube, to choke it, and, when the strug- 

 gles cease, devour it to the head. They seem to have 

 no choice as to the part seized, frequently catching 

 the prey by or near the head, and not choking it. I 

 watched to see how many Culcx larvae they would 

 eat, and found that the average was about three an 

 hour, one occasionally being killed between meals and 

 dropped whole on the bottom of the dish. They 

 are evidently of some use as exterminators, and not, 

 as a rule, a nuisance, though the occasional onsets of 

 even one, on the horse, made things lively at times. 

 The eggs of Psorophora are very large, ovate, and 

 coarsely sculptured. They are extremely resistant 

 to drying, and well fitted for over-wintering. 



From a long series of experiments with howardii 

 the following facts have been gathered. It seems to 

 be found a few days earlier than P. ciliata. The first 

 larvae are recorded April 30, one hour after a rain. 

 The eggs had evidently lain all winter and hatched 

 on being stirred up by this spring rain. They are 

 frequently thus found in newly formed pools immedi- 

 ately after a downpour. They will breed in drains, 

 though not in foul water. The first adult specimens 

 of the year were taken May 8, the last November 13. 



