April, '15] ALDRICH: SARCOPHAGID.^:, ECONOMIC RELATIONS 245 



nitida — the first from a pupa, the last two from adults. This was at 

 Norfolk, Va. 



On August 16, 1914, Mr. W. R. Walton, of the Bureau of Ento- 

 mology, near Cimarron, N. M., captured a female Sarcophaga in the 

 act of larvipositing on the body of an adult living specimen of Eleodes 

 hispilabris. In September of the same season, at Koehler, N. M., Pro- 

 fessor H. F. Wickham reared several specimens of the same fly from 

 adults of Eleodes tricostata and ohsoleta. In reply to an inquiry as to 

 the possibility of the fly larvipositing only on dead beetles, Professor 

 Wickham wrote: ''There is no doubt that all of the Eleodes of mine 

 from which Sarcophaga larvae were secured had already been infested 

 before being placed in the cages in which the food experiments were 

 carried on. These cages were all closed with wire screen over the tops, 

 the cages themselves being of the battery jar type. In most of them 

 the top had been made of wood with a central circular opening which 

 was covered with the wire mesh. . . . My practise was to take 

 an Eleodes out of the cage as soon as it was noticed to be dead and 

 place it in a vial covered with flne cheesecloth. Sometimes the larva 

 left the beetle within an hour or less, at other times it remained for 

 several weeks. In no case has a beetle been left where it could have 

 been 'blown' by a free fly." 



How the larva of Sarcophaga manages to penetrate the armor of 

 an adult Eleodes has not been ascertained. 



In November, 1914, at the University of Kansas, Mr. H. B. Hun- 

 gerford showed me specimens of an undescribed species of Sarcophaga, 

 which he had bred from adults of the longicorn Cottonwood Borer, 

 Plectrodera scalator, at Kinsley, Edwards Co., Kansas; the flies were 

 numerous, affecting 90 per cent of the beetles. 



A few scattering records may be added'. 



Human beings are occasionally affected, but in various ways: one 

 instance of intestinal myiasis, one of nasal, one larva in the ear, and 

 one in a tumor on the back, are on record in this country. None of 

 the species have been identified except the one in the intestine, which 

 was Ravinia trivialis, normally an excrement-feeding form. 



Sarcophaga helicis, as the name implies, was originally bred from a 

 snail. 



Undetermined species have several times been bred from tumors on 

 the neck of tortoises. 



Cole bred two undetermined species from rotting kelp on the sea- 

 shore at Laguna, Cal. (Pom. Coll. Jour. Ent., iv, 840). 



Only a few of the species so far have shown a wide range of adapta- 

 bihty in larval habit; but this may very likely be a conclusion from 

 too few cases. Helicis has been bred from a snail, Corydalis, Cicada,. 



