﻿June. 1895.] Clark. Food Habits of Beetles. 61 



ON THE FOOD HABITS OF CERTAIN DUNG 

 AND CARRION BEETLES. 



By Charles Upson Clark. 



It is not generally known, I believe, that many of the beetles fre- 

 quenting carrion and dung, feed to a greater or less extent on the mag- 

 gots — fly larvce — which they find therein. My attention was first called 

 to this habit two summers ago. While collecting from a from a dead 

 woodchuck which teemed with specimens of Silpha siirinameusis, I saw 

 a fly seized by one of the beetles, held up in the air and sucked dry. 

 Looking more closely, I discovered that the Silphas were feeding 

 on maggots, not as I had always supposed, on decaying matter. By 

 careful observations made since then at Charlemont, Mass., on beetles 

 found on dead squirrels and woodchucks and in dung, I have come to 

 the conclusion that these beetles may be roughly separated into three 

 divisions, according to the character of their food. 



In the first division — those which feed on the dung or carrion 

 wholly — I would place the Scarab^eidae, Copris, Trox, Geotriipes, 

 Aphodius, the Trichopteryx grade and Ct'rt^i^w and allied genera. It is 

 possible, of course, that these latter small beetles, some very minute, 

 feed on microscopic larvae, but they seemed to be feeding on the dung 

 or carrion. 



Then come those which feed on the maggots to a limited extent. 

 Such are Silpha americana and S. novehoracensis, Necrophonis, or- 

 bicollis, toinentosus and ainericaniis. 



The third division comprises those which feed almost exclusively 

 on larv^. Here belong Necrophonis marginatiis, Silpha lapponica, 

 S. siiri/iamensis, Hister immimis,fcedatus,fiertivi(s and depiirator, Sap- 

 riniis patruelis, Creophilus villosus, Listotrophiis cingulatiis , Staphy- 

 linus mysticus, fossator and Philonthiis sp. I have no doubt that 

 the smaller Staphylinidae so abundant in such situations are also animal 

 feeders, though I could not take them in the act. Clerus quadrigut- 

 tatus I have frequently taken devouring Scolytid larvae, and I feel sure 

 that Necrobia, Thaneroclerus, etc., will be found to feed on maggots. 



I hope that collectors in other localities will send the Journal 

 their observations on this subject. I cannot believe that the habit has 

 not been noticed before; but I can find no mention of it in the books I 

 have consulted, and I believe that collectors generally have gone on 

 the supposition that these beetles feed on the substances in which they 

 are found. 



