MYRMICA. 129 



Martineau record scabrinodis in nests of F. sanguined at Bewdley 28 , 

 and I have frequently found it with the same ant at Weybridge 

 and Woking. 



Crawley has found Myrmica scabrinodis (as also M . ruginodis 

 and M . laevinodis) invariably hostile to strange females 32 , even 

 when fertile and in cases where the colonies possessed no queens of 

 their own, and strange workers were always killed. On the other 

 hand I have known strange colonies of M. scabrinodis to amalga- 

 mate. Two colonies sent to me by Bouskell in October, 1911, from 

 Milt own, co. Kerry, were arranged in a four-chambered Janet 

 nest, so that each colony occupied two chambers at opposite ends, 

 the passage connecting them being plugged with cotton- wool. 

 One colony contained five females and workers, the other two 

 females, workers and brood. On January 12th, 1912, the cotton- 

 wool barrier was removed and the two nests allowed access to each 

 other. No fighting was observed, but on March 2nd some females 

 were dead. Later the remaining females and all the workers 

 occupied the two dampest chambers in common, and the two 

 colonies lived together on perfectly good terms, and in fact became 

 one 36 . 



M. scabrinodis (and also ruginodis and laevinodis) will readily 

 accept pupae of their own species from strange nests, and bring 

 them to maturity, but scabrinodis, at any rate, will not rear pupae 

 of the other species. 



Angus 14 records specimens of scabrinodis found in the stomach 

 of a green Woodpecker (Picus viridis] shot in January in North 

 Wales, Wasmann found the remains of thousands of workers in the 

 droppings of this bird in Holland 26 , and Chitty 23 mentions the 

 Tiger-beetle (Cicindela campestris) feeding on Myrmica rubra 

 (from what he told me the species was probably scabrinodis} . 



Dr. Sharp 19 describes the mechanism with which this species 

 stridulates as follows : 



" Myrmica scabrinodis (worker). England. The base or neck, of the seg- 

 ment behind the second node is quite short, and is at the sides covered with 

 sharply raised, quite irregular, rather short, transverse lines ; in the middle 

 there is a broad space appearing perfectly smooth and polished, but which, 

 under a high power, proves to be very regularly covered with straight, very 

 fine ridges. The perfect regularity of these fine lines is highly remarkable. 

 The edge, on the hind margin of the second node, by which these lines are 

 scraped is excessively thin." 



The males and winged females may be found in the nests from 

 June to September, and the marriage flight takes place chiefly in 

 August and September. Nylander 3 records a marriage flight of 

 this species at Borgoam in Emsalo on August 22nd, 1846 ; Forel 

 on the summit of Mont-Tendre on August 30th, 1871 ; Farren- 

 White 20 captured a male flying over the cairn which crowns the 

 head of Snowdon in August, 1879 ; Crawley and I noticed males 



