300 BRITISH ANTS. 



together after the marriage flight : colony -founding by Allo- 

 metrose 68 . [Wasmann's allometrose=an alliance between 

 females of different species or races to found a mixed colony.] 



A number of experiments have been carried out, in captivity, 

 on the behaviour of F. sanguinea females, when introduced to 

 colonies of F. fusca and its races, but only a few can be given here 

 to illustrate what takes place. 



In 1909 I carried out some thirteen experiments, only two of 

 which were successful, in all the others the sanguinea female was 

 either killed at once by the fusca workers or died subsequently from 

 injuries received from them. One difficulty in these experiments 

 is that it is not possible to provide a means for the female to escape, 

 as she could under natural conditions. In order to test this ques- 

 tion in the most exhaustive manner, we require a young female 

 just after her marriage flight, and also a small, or impoverished, 

 fusca colony, both of which are exceedingly hard to find, especially 

 just when wanted. I therefore made up small colonies of fusca, 

 and its var. glebaria, by putting a limited number of workers and 

 pupae into a combined " Fielde and Janet " nest, and introduced 

 sanguinea females. I used both old dealated and doubtless im- 

 pregnated females, and young winged virgin females, taken from 

 sanguinea nests. From the latter I removed the wings, as Wheeler 

 has shown that when the wings of a Formica female are removed, 

 she acquires the instincts of an impregnated female. 



No. 1. A small colony of F. fusca, consisting of workers and 

 larvae taken at Sherwood Forest on June 13th, 1909. June 24th, 

 a sanguinea female, taken in a nest at Aviemore on May 17th, 

 was introduced. She still retained one wing, which was removed. 

 The fusca workers ran away when the female first approached 

 them, but later attacked her. She retaliated by biting, and in the 

 evening they were still fighting. The female did not pay any 

 attention to the larvae, and did not try to conciliate the workers, 

 but ran away from them. June 25th, five workers had been killed 

 by the female, and the remainder were in the passage between the 

 two compartments with the larvae. June 27th the workers still 

 occasionally attacked the female, several of them were killed. 

 June 28th, the female appeared to be accepted by the workers, as 

 they were all resting together, and several were cleaning the female. 

 July 2nd, the female was dead, no doubt from injuries received 

 in the previous encounters. 



No. 2. July 4th, 1909, introduced dealated sanguinea female 

 taken at Woking, May 5th, into a small fusca colony with pupae. 

 The female approached the pupae, tapped them with her antennae, 

 and was evidently much interested in them. The workers removed 

 the pupae, but the female was only slightly attacked, and repulsed 

 the workers. A little honey was given to the ants, and the female 



