106 Zoologica: N. Y. Zoological Society [HI; 3 



that were attending the aphids 'and did not mind one or two 

 actually standing up and examining its legs to see who was 

 there. The ants did not attack it in any way.' " 



A comparison of the behavior of the insects considered in 

 the foregoing paragraphs is very instructive. The predilection 

 of ants for various Homoptera (aphids, coccids, membracids, 

 cercopids and psyllids) is well known. Though never observed 

 among the predatory Dorylinje and Cerapachyinse and rare among 

 the Ponerinaj and Pseudomyrminse this predilection is, neverthe- 

 less, so prevalent among the higher subfamilies (Myrmicinse, 

 Dolichoderins and Formicinae) that it has not escaped the most 

 casual observer. When this type of behavior is highly developed, 

 as in our species of Lasius. the ants display not only an exquisite 

 deftness in stroking their trophobionts but also a decidedly pro- 

 prietary interest in them, most clearly evinced by building 

 peculiar carton or earthen shelters over them, aggressivelj' 

 defending them from their foes, or even collecting them and 

 their eggs in the nests, distributing them over the surfaces of 

 suitable plants and conveying them to places of safety when the 

 colonies are disturbed. The whole performance is so elabo- 

 rately adaptive as to suggest on the part of the ants an intimate 

 acquaintance with the requirements and habits of their wards. 

 This is also indicated when the latter fail to respond to stroking, 

 for the ants do not wear themselves out by prolonged solicitation 

 after their cattle have discharged their honey-dew, but stand 

 around as if waiting for more of the saccharine liquid to 

 accumulate. 



The wasp described by Belt and the butterfly described by 

 Bingham are really robbers, the former having learned to dispos- 

 sess the ants of their wards, at least temporarily, the latter to 

 overreach the ants and obtain the honey-dew by stealth. Though 

 very different, the relations of the beetles to their coccids are no 

 less extraordinary. The case is, indeed, so far as known, unique 

 among the Coleoptera. Unlike many species of ants, the beetles 

 have not yet learned to pick up the coccids and carry them about, 

 but merely accept them as an integral part of the normal environ- 

 ment or as members of the colony. The fact that the beetles 

 clearly recognize the signal of the prospective emission of the 

 honey-dew by the coccids, when they raise their caudal segments, 



