FORMICA. 283 



banks, in rotten stumps, under stones, in clumps of grass, on and in 

 mud walls, under and at the roots of heather, and sometimes small 

 nests will occur under an old boot, or anything lying about. 



In summer its nests are often covered with cut grass and other 

 vegetable refuse (Schenck says especially the scales of beech 

 buds) 11 the debris never forming a hillock, but only a carpet 

 an inch or so high. 



F. sanguined is fond of a new nest ; in the summer it selects open 

 sunny places, and in winter more sheltered spots ; this change of 

 nests takes place in very hot dry weather, and also at the approach 

 of winter ; but sometimes it only extends its nest deeper into the 

 ground this is generally the case with colonies nesting in old 

 stumps. On July 4th, 1914, I found a colony of this ant at Wey- 

 bridge, situated in a hole in the turf ; on August 3rd they had 

 moved to a nest, about six yards from the former one, at the roots 

 of heather with debris chiefly consisting of chopped heather laid 

 over it. On August 24th I witnessed the ants moving again, 

 carrying their fellows, pupae, etc., to a spot at the root of a gorse- 

 stem some six yards from the heather nest, and by September 15th, 

 they had all gone underground for the winter. 



Escherich has called the summer nests " work -nests," and the 

 winter ones "rest-nests," 56 and I have found in Britain that 

 sanguined rarely appears above ground before May, and often 

 retires in September for the winter. 



A colony may possess three nests, and Forel says they will pass 

 the winter in one of these one year and in another the next 24 . 

 I have found these ants nesting in sandy banks, with or without 

 a covering of vegetable detritus, in grass clumps, in old stumps, 

 and at roots of gorse, etc. (at Woking) ; under and at the roots of 

 heather and in fir-stumps (at Weybridge) ; simply emerging from 

 a small hole in the turf (in Guestling Wood and at Hind Head) ; 

 in the earth on the top of an old mud wall (in the New Forest) ; in 

 large tree-stumps (near Leighton Buzzard) ; under rather loose 

 small stones on a railway embankment, and in banks covered with 

 thick layers of plant refuse, on the borders of hedges at the side 

 of roads (at Bewdley) ; under large stones by the side of a wall, 

 with a little vegetable debris scattered about (on a moor at Ran- 

 noch) ; and under one or two very large heavy stones by the side 

 of a path (at Aviemore). Sometimes very large colonies may 

 occur ; Wasmann records that at Exaeten in Holland four hundred 

 and ten colonies were present, on an area of four square kilometres, 

 consisting of over one thousand nests 50 , and at Luxemburg he 

 found thirty-nine colonies in one spot two hundred metres in 

 length and one hundred in breadth 62 . At Woking a dozen or so 

 nests usually occur over a small area, most of which probably 

 belong to the same colony, but at Bewdley, in 1909, a large number 

 of colonies were present, nests being found all along the railway 



