Parasitic Beetles. 417 



Motschulsky, and Schiodte being conspicuous among them. 

 In spite, however, of the numerous observations that have been 

 made, and of the extension among British Coleopterists of 

 acquaintance with these beetle-ant connections through collect- 

 ing operations, no satisfactory explanation has been given for 

 them. It has, indeed, been suggested that the Coleoptera, and 

 especially those of the section Braclielytra, resorting to the 

 nests may be in some way conducive to the welfare of the 

 communities, in all probability yielding secretions which serve 

 as food to the young brood. But this view appears to me to 

 reverse the case. It is surely more likely that the beetles find 

 in the secretions of the ants or in the materials of which they 

 form their nests, or in the food which they procure for their 

 young brood, a sufficient attraction to induce them, as free 

 agents, to take up their abode with the latter. On the other 

 hand, in two instances, at least, viz., Claviger testaceus and 

 Atemeles, there can be no doubt that their landlords are as 

 careful over them as their own young, bearing them rapidly, 

 but with an excess of care, away from the approach of danger, 

 and exhibiting as much anxiety on their account as some of 

 their species do for the Aphides, to whose secretions, so agree- 

 able to the ants, it is possible that those of the beetles may be 

 similar. It is certain that the larger Braclielytra frequenting 

 ants' nests acquire a most peculiar and pungent odour, and that 

 they often distil an iodine-coloured fluid on the cards on which 

 they are mounted, and retain a like smell for a considerable 

 period. This, evidently (from its similarity of smell) derived 

 from constantly dwelling in a vapour of exhalations of formic 

 acid, may, on the principle of " similia similibus," be accept- 

 able to the ants, whose ingenuity may succeed in ct tapping " 

 the internal supply, though there is no visible outlet as in the 

 Aphides. Apart from this interpretation, there remains no 

 solution for the enigma but that of sentimental attachment, 

 which is rather too absurd for such work-a-day folk as the 

 Formicidce. No verbal expression could, nevertheless, suffi- 

 ciently depict the evident trouble and anxiety with which a 

 Formica fusca carries away Atemeles emarginatus in its jaws, 

 tenderly bearing it ; and there is something ludicrous in the 

 complacency of the beetle, a great, angular Brachelytron, as it 

 submits to be thus dandled; the absurdity of the thing being 

 more apparent when one compels the ant to drop its nurseling, 

 which straightway opens out its long legs and antenna?, and, 

 considerably larger than its late porter, scuttles away with 

 straggling gait. 



The British ants which have hitherto been observed to har- 

 bour beetles in their nests are Formica rufa, F. congerens, F. 

 fusca, F. fuliginosa, F. flava, F. sanguined, and Myrmica rubra. 



VOL. X. NO. VI. E E 



