OF WASHINGTON. 311 



bass and other fish. The insect is thus of some slight economic 

 importance and derives some additional importance from the 

 fact that while it is eaten by large fish, it retaliates by destroying 

 smaller fish. No natural enemies of this species have ever been 

 recorded. The species breeds rather abundantly in the Potomac 

 river and in Rock Creek, and the egg-masses, looking like acci 

 dental splashes of whitewash, are often seen on the rocks along 

 the shores of these streams. 



In the latter part of July of the present year, Mr. R. S. Clif 

 ton, of the Division of Entomology, an enthusiastic boatman, 

 noticed that certain egg-masses upon rocks on the Virginia side 

 of the Potomac river above Georgetown contained small round 

 holes, and suspected from this fact the existence of some parasitic 

 or predaceous enemy. Upon close examination he saw a small 

 beetle engaged in eating into an egg-mass. He did not capture 

 the specimen, but, thinking that the observation might be of im 

 portance, he mentioned it to the writer, who, on August 4, 

 joined him in an investigating expedition. This was about two 

 weeks after the original observation. At the date of our visit 

 we found hardly one egg-mass out of a very large number which 

 had not been eaten into. The beetle was captured and later de 

 termined by Mr. Schwarz to be a variety of Anthicus halde- 

 mani. * Upon opening the egg-masses we were greatly interested 

 to find the larva of the beetle. In some cases only one or two 

 large larvae were found in a single egg-mass ; in other cases a 

 large number certainly more than a dozen smaller larvae were 

 found, and in others larvae of several distinct sizes w r ere noticed. 

 Living specimens were brought home and fed in confinement. 

 It was at first supposed that the larvae would transform without 

 issuing from the eggs. This, however, proved to be incorrect. 

 When fullgrown they wandered restlessly around and this fact 

 was sufficient to indicate to Mr. Pergande, in whose care they 

 had been placed, that they needed certain conditions for pupat 

 ing which were not present in the open-mouthed vials in which 

 they had been kept. He therefore transferred them to vials con 

 taining sand, into which they immediately crawled and in which 

 they soon pupated. Two larvae were placed with the sand on 

 August 15. On August 19 they were still unchanged, but one 

 of them had formed a kind of cocoon from the grains of sand. 

 On August 22 this individual had transformed to pupa. On 

 August 24 Mr. Schwarz went with Mr. Clifton to the same 

 locality and secured further material. August 31 three larvae 

 obtained on this trip transformed to pupae, and September 3 



* Later Capt. Casey informed the writer that the species is his A. her- 

 oicus, described in Annals N. Y. Ac. Sc., 8, 1895, p. 712. 



