86 BRITISH ANTS. 



13th he noticed F. nitidulus following, in files, in the track of the 

 F. pratensis, carrying their winged females, workers, and brood 

 and not experiencing any difficulty in finding the way. 



When a Formicoxenus carries another worker, it holds the latter, 

 not (as a Formica would) under its body, but (as other Myrmicinae 

 do) over its back. 



Nylander 1 described F. nitidulus so long ago as 1846, but the 

 male remained unknown until 1884 when it was discovered by 

 Adlerz 14 in Sweden. This sex was not recorded from Britain till 

 1906, when Bagnall 28 captured some ten examples in nests of 

 F. rufa at Corbridge-on-Tyne on August 12th, and in July and 

 August, 1910, more males were taken by Arnold 31 and Hamm, 

 from what was evidently a large colony, in a rufa nest in the New 

 Forest (there is however an unrecognized male in the Rothney 

 Collection at Oxford, doing duty as a worker of Stenamma wesi- 

 woodi this was taken by Dr. Power at Wey bridge on July 24th, 

 1864 34 ). On September 6th, 1912, I secured a number of males 

 from a nest of F. rufa at Weybridge 33 , in which Formicoxenus had 

 occurred for many years past. The day was dull and cloudy and 

 the males were observed running about on the surface of the rufa 

 nest ; they were easily distinguished from their own workers, by 

 their more active and restless habits, and the bent funiculi of the 

 antennae. These males endeavoured to copulate with the deflated 

 females, and also with the workers, climbing on to their backs and 

 grasping them round the thorax with their short mandibles, both 

 on the surface of the nest and in my tubes on September 14th 

 six more males were found in this nest 34 . Wheeler 32 describes the 

 mating of this species, which he observed in the Upper Engadine 

 in July, 1907, as follows : 



" After a cold night, the sun remained behind a mass of clouds 

 at about 9 a.m. when I saw dozens of Formicoxeni of all three 

 phases, but mostly males, running hither and thither over the 

 small twigs and other debris forming the outer covering of an old 

 rufa nest which I had stopped to examine. The males moved very 

 quickly, with feverishly vibrating antennae, and were so amorous 

 that they often seized workers and attempted to mate with them. 

 The few winged females were soon supplied with partners and the 

 supernumerary males continued to hurry about over and among 

 the little sticks of the nest. Then the sun suddenly emerged from 

 the clouds and, as if by magic, all the Formicoxeni disappeared into 

 the nest. I waited for some time and during the remainder of the 

 morning returned repeatedly to the spot, but none of the tiny 

 inquilines reappeared." 



It will thus be seen that the males may be found in July, August, 

 and September, and the winged females in July and August (I 

 have only once taken the winged female in August, 1906, at 

 Bournemouth). 



