June, I9IS-] MISCELLANEOUS NOTES, 151 



the object of procuring the skull of the porcupine and was surprised 

 to find that within two hours many Silf^ha lapponica and some Necro- 

 phonis tomciitosits and Necrophorus orbicollis had arrived. I was 

 still more surprised to find many of the Silpha surinamensis engaged 

 in extracting fly larv?e from the carcass and devouring them as 

 rapidly as possible. Crcopliilus viUosus was busy in the same way, 

 but I did not observe that Silpha amcricana ate any of the larvae. 



The porcupine was visited again the next day, when Silpha suri- 

 namensis was found to be still busy catching fly larvse, and I saw 

 scores of them pulled from their hiding and devoured while still 

 wriggling. Creophilits z'illosiis was equally active and individuals of 

 both species could be seen running about, each with a larva in its 

 mandibles. They would often seek some quiet place to devour the 

 tender grub. On one low plant I saw three surinamensis each one 

 devouring a larva, but they usually did not climb on anything, but 

 sought some retreat on the ground, while others were content to de- 

 vour their captives while stationed on the remains of the porcupine 

 and among the moving throng of their companions. It was difficult 

 to say which was the more active in larva; catching, Silpha surina- 

 mensis or Creophilus z'illosus. At one place I saw some Silpha 

 surinamensis feeding on one of the legs of the porcupine, but the 

 majority were undoubtedly in quest of fly larv?e. Thousands of the 

 larvae that were engaged in devouring the putrid porcupine were 

 thus destroyed and their good work cut short. 



It is known that the habits of the members of both of the fami- 

 lies Silphidce and Staphylinidre are quite varied, and this note merely 

 emphasizes the fact more strongly that these beetles are not as gen- 

 erally beneficial as some of the text books state. — Wm. T. Davis. 



Dicerca obscura and Dicerca lurida. — During the past summer I 

 took in Virginia on persimmon some fifty odd specimens of Dicerca 

 obscura and at same time took on hickory numerous specimens of 

 D. lurida. In life, the appearance of these two species is so dif- 

 ferent that they can be distinguished at a glance. In obscura, the 

 ground color is blacker, the elevated portions more shiny, the pruin- 

 osity in the depressed portions whiter; in lurida, the ground color is 

 coppery, the pruinosity grayer. When, however, a specimen has been 

 pinned for a couple of months, these differences become less and 



