Sept., 1908.] Wheeler : Studies on Myrmecophiles. 141 



some scurrying ant intent on more important business. Then the 

 beetle lies for a few moments with sprawling legs but soon succeeds 

 in righting itself and either scampers away or at once strikes its 

 favorite attitude again. It seems to be greatly aided in the righting 

 movements by the peculiar position of its tarsi, which are strongly 

 flexed backward on the tibiae, so that when it is lying on its back, the 

 claws are brought into the most advantageous position for taking hold 

 of the floor of the nest. 



Like the European ferrugineus, If. brunneipennis also feeds on solid 

 substances. It eagerly seeks out any dead or wounded ants on the 

 refuse heap of the nest and may be seen gnawing at their joints or 

 mouth-parts or eating its way into the soft parts of the gaster after 

 having made a large hole in the chitinous investment. It will also 

 spend hours gnawing away with its sharp little mandibles at the bodies of 

 caterpillars and other insects that have been partially eaten by the ants. 

 Occasionally the body of a single small caterpillar or dead ant will be 

 covered with the beetles, all busily feeding. At such times the ants 

 often come up, tear them away and feed them with regurgitated food. 

 The beetles straighten up and patiently submit to the fondling, licking 

 and feeding, but as soon as the ants move away, return to their ghoulish 

 repast. 



May 31 I introduced two living Tliecla caterpillars into the nest and 

 observed them in the act of exuding droplets of liquid from the mouth- 

 like orifice in the mid-dorsal line of their penultinate segment. The 

 ants eagerly imbibed these droplets and, to my surprise, some of the 

 Hetcerii crawled up onto the backs of the caterpillars, detected the gland 

 and drank the exuding liquid. By the following day one of the cater- 

 pillars had pupated and had been deposited on the refuse heap, the other 

 had been killed and reduced to a shriveled skin by the hungry ants. At 

 this skin the beetles were busily gnawing when I uncovered the nest. 



The beetles never made any attempts to leave the nest but seemed 

 to be well satisfied with their board and lodgings. May 31 two of 

 them were in copula, but no eggs nor larvae were subsequently seen. 

 Towards the latter part of June the beetles died off one by one till 

 June 30, when only a single individual survived. On this date I was 

 compelled to discontinue my observations. 



The foregoing notes show that H. brunneipennis of the Eastern 

 United States is a true symphile, since, unlike the European ferrugi- 

 neus, it is treated with marked friendliness and is actually fed by its 



