416 WILLIAM M. MANN 



hut with neogagates the attacks were not so fierce. Several 

 times workers were observed licking her, and she was twice 

 observed feeding a worker. She was finally killed. 



Viehmeyer (40) studied the mating flights in several species of 

 ants. These flights have a double purpose, to distribute the 

 species and to prevent close inbreeding. The flights of the 

 same species occur at approximately the same time, and at 

 these times sexual forms from many nests mingle together in 

 an enormous swarm, so that the individuals from one nest 

 copulate with those from another. The wings of queen ants 

 are very brittle and w T eak, and the presence of a strong wind 

 blows the ants about, scattering the species to long distances. 



Often many species of ants have their mating flight at the 

 same time, and join in one common swarm. One of these 

 swarms was observed by Viehmeyer. It consisted of two spe- 

 cies, Myrmica scabrinodis and M. ruginodis, with the latter 

 greatly predominating in numbers. When numbers of pairs 

 had fallen to the ground they were collected. Of the lot, only 

 about one-sixth were of the same species, and in every case 

 these were ruginodis. Most of the couples consisted of a scab- 

 rinodis queen and a ruginodis male. The males of both species 

 predominated in numbers over the females. Hybrids between 

 ants are sterile, and Viehmeyer does not consider that hybridi- 

 zation has any importance in the phylogenetic history of the 

 species. 



Wasmann (42) treats, in a very general way, ants and their 

 guests, dealing especially with social parasitism of the former, 

 and the relations of the latter to their hosts. Some two thousand 

 species of Myrmecophiles have been recorded. These Wasmann 

 has separated, according to their relations to the host, into 

 five classes, (1) Symphiles, or true guests; (2) Synoeketes, or 

 indifferently tolerated guests; (3) Synechthrans, or persecuted 

 guests; (4) Ecto- and endoparasites, and (5) Trophobiotic sym- 

 philes. A short account of the Symphiles is given. With the 

 legionary, or driver ants are three types of guests, called by 

 Wasmann symphilic, mimetic and protected ("Trutz") types. 

 The latter are tolerated by the ants because they are unable to 

 destroy them. This paper is a very excellent general account 

 of the subject, and is illustrated with several photographic plates. 



