LASIUS MIXTUS, NYL., IN BRITAIN. 237 



(b). Tibiae without exserted hairs. Head, thorax 



and abdomen with only short hairs. Scale 



less high than in umhratua, but higher than 



in fiavus, often feebly emarginate at the top. 



, 1. o-5mm.-4mm. .. .. .. .. Race /.. »iia;<)(s, Nyl. 



Females. 



A. Head small, not as broad as the thorax, without 



distinct emargination behind. Thorax broad; 

 abdomen much broader than the thorax. Size 

 very large in comparison with the worker . . L. daviia, Fab. 



B. Head broader than the thorax, strongly emarginate 



at the hind border. Thorax fairly narrow. 

 Wings clouded with brown as far as the middle. 

 Abdomen only a little broader than the thorax. 

 Size less large in comparison with the worker . . L. umbratus. 



(a) Tibiae with exserted hairs. The upperside of the 



thorax and abdomen abundantly provided 

 with short and flat hairs. Of a brown red ; 

 mouth, antennse, and legs lighter. Scale 

 generally emarginate. 1. 7mm. -8mm. .. L. in(i7;/v(ii(.s, 1, spec. Nyl. 



(b) Tibiae without exserted hairs. Thorax nearly 



without hairs on the upperside. Abdomen 

 with only a little short hair. Colour the 

 same as in the preceding, but the underside 

 of the head and thorax, as well as the meta- 

 notum and nearly the whole of the scale are 

 reddish, clear. 1. 6mm. -8mm. .. .. Race, L. */tf.c^i(s, Nyl. 



Males. 



A. Terminal edge of the mandibles with one large tooth 



in front .. .. .. .. .. .. L.Jlavus, FslTo. 



B. Terminal edge of the mandibles with five teeth. 



Brown-black. Frontal furi'ow always distinct. 



Wings clouded with brown as far as the middle. 



1. 4mm.-4-5mm. Head large .. .. .. L. umbratus. 



{a) Eyes distinctly hairy .. .. .. .. i. um^^ra^ws, 1 spec. Nyl. 



(h) Eyes almost without hair . . . . . . Race, L. mixtua, Nyl. 



In 1897 Mons. Charles Janet published an admirable paper, Sur le 

 Lasiufi mixtus, at Limoges. He gave a long account of the habits of 

 this ant, and also of the Myrmecophiles he found with it. Most of 

 the same species occur also with L. iwibratns. I have found the 

 following Acari with the latter in Britain, all of which Mons. Janet 

 records with L. inixtus at Beauvais. 



Uropoda ovalis, Koch, fixed on the femora of the ants in a nest 

 from Weybridge. 



Cilibano comata, Berlese, on the larvae of the ants in a nest at 

 Woking. 



Trachi/ uropoda boatocki, Mich., in some numbers in a nest at 

 Whitsand Bay. 



Antennuphorns nhliiianni, Haller, in large numbers on the ants in 

 the nest at Woking. Only two specimens have ever been taken before 

 in Britain ; this was by Michael in Cornwall. 



Sphaerolac'laps holotlnjroidea, Berlese {Neoherlesia sp. ? of Mons. 

 Janet's paper), in nests at Bewdley, Wellington College, Woking, 

 Weybridge, Box Hill, etc. 



Uropoda pihiloctena, Trouessart, fastened to the strigil of the ants 

 in the nest from Weybridge. Mr. Crawley has also found it on his 

 ants from the same nest. This species is new to Britain. There are 



