52 



the females and males leaving the nest, which was in a stump-, 

 and running up the twigs, where copulation took place. 



Occasionally, however, deälated females are found wandering 

 about in localities some distance from nests of L. fuliginosus, 

 Crawley found one at Oddington, near Oxford, about loo yd, 

 from a nest, and another near Esher in August 1899, where 

 there was no nest near. In such cases as these, females would 

 not be likely to be received back into their nests. However, 

 when isolated, they display no desire to build cells in the manner 

 of the normal founding species. Crawley, in May 1905, isolated 

 some newly-deälated females at Ouchy, and put others with 

 workers from their own nest, but none of the females settled 

 down, and the workers did their best to escape. Eventually 

 all the females perished. From the above facts alone, therefore, 

 it seems doubtful that the iemsle L. fuliginosus can found a colony 

 unaided. Several discoveries in nature point to L.^unibratus 

 or L. mixtus being the host-species of L. fuliginosus. Donis- 

 THORPE found at Lymington in 1897 a large colony of L. fuliginosus 

 in a hollow tree, and L. umhratus was undoubtedly living with it, 

 as workers of both species were going in and out of the same 

 holes. 



Crawley, in 1898, repeatedly found workers of L. umhratus 

 walking unmolested with the workers of a large nest of L. fuli- 

 ginosus estabhshed under his house near Oxford. Some of these 

 L. umhratus were placed in an observation nest composed of 

 workers and larvae from the above colony of L. fuliginosus. 

 They lived for some time in the nest, were fed b}^ the L. fuliginosus 

 and tended the larvœ, and were only occasionally attacked. 

 In September 1900 Tuck sent to Donisthorpe a worker of 

 L. umhratus taken in a nest of L. fuliginosus at Bury St. 

 Edmunds. 



In 1904 de Lannoy found at Knocke-sur-Mer a few workers 

 of L. mixtus in the midst of a large colony of L. fuliginosus, and 

 on good terms with the workers of the latter. 



In 1906 he again found workers of L. mixtus in several L. 

 fuliginosus nests. Forel and Emery, commenting on de 

 Lannoy's observations, expressed the opinion that the presence 

 of these L. mixtus workers was due to the fact that fertile L. 

 fuliginosus females had entered nests of the former species 



