CARRION BEETLES. 



in cross-section, regularly oval in outline, and .6 in. long. 

 It is common in brackish pools. 



Plate LXXV is sufficient help for the identification of 

 Silpha and Necrophorus, the only two genera of this 

 family which ordinarily attract notice as Carrion Beetles, 

 although there are not only numerous small species which 

 feed on carrion but some on decaying fungi and a few are 

 found only in ants' nests. There are six ventral abdominal 

 segments; the front coxas are conical, prominent, and, 

 except in eyeless species found in caves, nearly or quite 

 touch each other. 



Species of Nccroplwrus are called Burying 

 Necrophorus 



Beetles. So many have testified, either from 



hearsay or from observation, to their burying small car- 

 casses and feeding on them under ground, that it must be 

 true. Probably I have been unfortunate: I have fur- 

 nished them with numerous carcasses but they ate 

 them all on top of even loose sand. Perhaps the right 

 species did not come to my feast. The sensory pits in the 

 enlarged portion of the antennas are doubtless olfactory 

 and explain the insects' quickness in locating their particu- 

 lar kind of food. They are all black, usually marked 

 with red or yellow. The following three species of 

 Necrophorus have their hind (and, to a lesser extent, their 

 middle) legs bowed. N. americanus: an inch or more long; 

 pronotum rounded; orange- red on vertex of the head, 

 central part of pronotum, two irregular spots on each ely- 

 tron, and club of antennae. It usually feeds on reptiles. 

 N. sayi: less than an inch long; pronotum rounded; orange- 

 red in a cross-bar near base and a spot near apex of each 

 elytron. Not usually common. N. marginatus: (Plate 

 LXXV) the elytral spots are sometimes connected along 

 the margin, the basal spot sometimes divided. One of 

 the commonest. The following three have straight legs. 

 N. orbicollis: marked much like sayi. N. pustulatus: 

 pronotum transversely oval, very little narrowed behind; 

 orange-red on antennal club and two spots, the apical 

 one sometimes double, on each elytron. Wholly black 



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