332 WHEELER— ANT LARV^. 



of amical selection. The same reasoning is, of course, made to 

 apply, mutatis mutandis, to Clavicjcr tcstoccus which lives with 

 Lasiiis flavus, the Paussids which live with different species of 

 Pheidole, the physogastric Staphylinids which live with various 

 termites, etc. The bizarre structures of these symphiles, such as 

 the antennse of Clavigerids and Paussids, are compared with the 

 deformities of some breeds of domestic animals and are supposed 

 to have arisen and to have been perfected in an analogous manner. 

 The analogy, as conceived by Wasmann, is indeed so close that it 

 is hard to see why the term amical selection should have been intro- 

 duced for what would seem to be after all only another case of 

 Darwin's artificial selection though performed by ants instead of 

 men. 



The argument looks plausible till we examine it more critically. 

 When we ask how the particular symphilic instinct to foster Lome- 

 chusa became established i. c, hereditary, in sanguinea, we see that 

 Wasmann has taken a great deal for granted. Of course, we really 

 know nothing about the phylogeny of sanguinea in its relation to 

 Lomechnsa. The sanguinea queen and her fertile female offspring 

 in colonies that are old enough to be infested by the beetle, pay no 

 particular attention to the parasite and could therefore acquire such 

 an instinct as Wasmann postulates only by inspiration. The 

 workers, which do look after the beetles, rarely reproduce and prob- 

 ably never reproduce in infested colonies and would therefore not 

 be in a position to transmit even if they acquired such an instinct. 

 And as the sanguinea brood is either largely devoured or converted 

 into infertile pseudogynes, so that the whole colony tends to die out, 

 we have "anything but a favorable environment for engendering and 

 transmitting an instinct so specialized as to be concerned with a par- 

 ticular symphile. Furthermore, Lomechusa is a very sporadic para- 

 site. It may be abundant in certain regions, as in certain parts of 

 Holland, where Wasmann has worked and at St. Moritz, in the 

 Upper Engadin of Switzerland where I once found it and its larvae 

 in considerable numbers, but there are many regions in which the 

 sanguinea colonies are entirely free from the pest and hence in a 

 flourishing condition and one most favorable to the survival of the 

 species. Wasmann has not shown that Lomechusa introduced into 



