168 Chapter IV. 



if they had but a spark of intelligence, sad experiences 

 would have enlightened themf long ago on the folly 

 of this mistake. Nay more, if the pseudogynes owed 

 their origin to the normal nursing instincts of ants, 

 we should have to despair of the fitness of animal 

 instinct and even of the wisdom of the Creator. What 

 is the key to this mystery? It is the beetle Lomechusa 

 strumosa. According to our hypothesis the rearing 

 of the pseudogynes is an aberration of the breeding 

 instinct of ants, caused by the continuous education 

 of Lomechusa-larvae. In the economy of nature it 

 is the duty of this beetle, to check the excessive 

 increase of the ant-species, whose hospitality it enjoys. 

 For this reason its larvae not only consume countless 

 ant-eggs and ant-larvae, the ants calmly looking on 

 the while, but by destroying the offspring of the 

 ants, and by the care which the ants bestow on them, 

 they cause the degeneration of the normal nursing 

 instincts of the workers, resulting in the education of 

 crippled pseudogynes. 1 To account for these facts on 

 the score of "individual animal intelligence" would 



*) These expositions will probably suffice also to refute an objection 

 raised by Dr. G. Adlerz, who, misunderstanding my psychological ex- 

 planation of the rearing of pseudogynes, says in the third part of his 

 valuable "Myrmecologiska studier" (Stockholm, 1896), p. 51: ^With 

 regard to this Wasmann seems inclined to credit ants with an exag- 

 gerated power of reflection, which he otherwise is unwilling to do." 

 Besides, the pathological degeneration of the breeding instinct explains, 

 why the rearing of pseudogynes is still continued, even when colonies 

 have been deprived of their Lomechusas. By the way, let me repeat 

 a remark formerly made, that the causal connection of pseudogynes with 

 the Lomechusas is not to be confounded with the explanation of this 

 connection. The former seems to be firmly established by direct obser/a- 

 tion, the latter is still an hypothesis, but an hypothesis, strongly con- 

 firmed by recent experiments of myself and of Vichmeyer. See "Neue 

 Bestaetigungen der Lom^c/tw^a-Pseudogynentheorie" ("Verhandlungen 

 der Deutsch. Zool. Gesellsch.," 1902, p. 98 ff.). 



