226 COLEOPTERA 



apparently secrete some substance with a flavour agreeable to the 

 ants, which lick the beetles from time to time. On the other 

 hand, the ants feed the beetles ; this they do by regurgitating 

 food, at the request of the beetle, on to their lower lip, from which 

 it is then taken by the beetle (Fig. 82). The beetles in many 

 of their movements exactly resemble the ants, and their mode 

 of requesting food, by stroking the ants in certain ways, is quite 

 ant-like. So reciprocal is the friendship that if an ant is in 

 want of food, the Lomechusa will in its turn disgorge for the 

 benefit of its host. The young of the beetles are reared in the 

 nests by the ants, who attend to them as carefully as they do to 

 their own young. The beetles have a great fondness for the 

 ants, and prefer to sit amongst a crowd thereof; they are 

 fond of the ants' larvae as food, and indeed eat them to a 

 very large extent, even when their own young are receiving 

 food from the ants. The larva of Lomechusa, as described by 

 Wasmann (to whom we are indebted for most of our knowledge 

 of this subject), 1 when not fully grown, is very similar to the 

 larvae of the ants ; although it possesses legs it scarcely uses 

 them : its development takes place with extraordinary rapidity, 

 two days, at most, being occupied in the egg, and the larva 

 completing its growth in fourteen days. Wasmaun seems to be 

 of opinion that the ants scarcely distinguish between the beetle- 

 larvae and their own young ; one unfortunate result for the beetle 

 follows from this, viz. that in the pupal state the treatment that 

 is suitable for the ant -larvae does not agree with the beetle- 

 larvae : the ants are in the habit of digging up their own kind 

 and lifting them out and cleaning them during their meta- 

 morphosis ; they also do this with the beetle-larvae, with fatal 

 results ; so that only those that have the good fortune to be 

 forgotten by the ants complete their development. Thus from 

 thirty Lomecliusa larvae Wasmann obtained a single imago, and 

 from fifty Atemeles larvae not even one. 



Many other Staphylinidae are exclusively attached to ants' 

 nests, but most of them are either robbers, at warfare with the 

 ants as is the case with many species of Myrmedonia that lurk 

 about the outskirts of the nests or are merely tolerated by the 

 ants, not receiving any direct support from them. The most 



1 Verglcichende Stttdien iiber Ameisengciste, Nijhoff, 1890 ; and T-ijdschr. ent. 

 xxxiii. 1890, pp. 93, etc. ; Biol. Centralbl. xv. 1895, p. 632. 



