84 BRITISH ANTS. 



Original description of Myrmica nitidula Nylander [Acta. Soc. 

 Sc. Perm. 2 1058 (1846)] :- 



" ^ laevis tota nitidissima nuda, rufa, abdomine fusco, oculis atris ; antennae 

 12-articulatae; thorax supra convexiusculus longitudine abdominis (praeter 

 petiolum), metathorax a mesothorace inipressione transversal! discretus, 

 metanoto in dentem validiusculum horizontalem utrinque exeunte ; nodus 

 petioli posterior antice infra spinula minuta instructus. Corpus pilis nonnullis 

 subtilissimis. Statura et magnitude proxime Myrmicae muscorum. Ab 

 omnibus congeneribus supra allatis abunde discedit haec species jam capite, 

 thorace nodisque petioli politis, propriaeque referenda est subdivision! Oper- 

 arium in acervo formicae cujusdam rufae prope Helsingfors invenit ad 

 determinandumque mutuam dedit Stud. F. W. Maeklin. Ex unico specimine 

 notas ulteriores dare nequeo." 



Habitat. 



Formicoxenus nitidulus is found in North and Central Europe 

 and West Siberia in the nests of Formica rufa and pratensis. 

 Wasmann discovered a colony with the latter in Luxemburg, all 

 the individuals being of a dark brown colour, to which he gave the 

 varietal name of picea 24: . 



Hants, S. : New Forest (G. R. Waterhouse) 5 ; Bournemouth 

 (Jackson) 25 . 



Kent, E. : Blean Woods (Cliitty and Donisthorpe) 22 . 



Surrey : Weybridge (G. R. Waterhouse) 5 ; near Guildford 

 (Capron) 18 ; Shiere (Capron) 19 ; Guildford (Smith) 12 ; Esher 

 (Champion) 19 ; Oxshott (Bedwell) ; Camberley (Donisthorpe). 



Berkshire : Wellington College (Barnes) 2 * ; Tubney (Collins). 



Worcester : Bewdley (Blatch) 21 . 



Warwick : Knowle (Ellis) 23 . 



Yorks, N.E. : Scarborough (Lawson) B . 



Durham : Chopwell Woods (Bagnall) 30 . 



Northumberland, S. : Corbridge-on-Tyne and Hexham (Bagnall) 21 . 



Cumberland : Keswick (Day). 



Easterness : Nethy Bridge (Donisthorpe)^. 



This small ant was added to the British list in 1857, by G. R. 

 Waterhouse 5 , who took specimens in the nests of Formica rufa at 

 Weybridge, and in the New Forest. It is a myrmecophilous species 

 only occurring in the nests of its hosts F. rufa and pratensis, though 

 Wheeler 32 (p. 434) suggests that it may once have been a guest of 

 Myrmica rubida (as Symmyrmica chamberlini Wheeler, an archaic 

 form of Formicoxenus found in Utah, lives with Myrmica mutica, 

 a species closely related to M . rubida) and only later became 

 attached to Formica rufa. He goes on to say : ' This is suggested 

 by the fact that the present host belongs to a different subfamily 

 and by the extreme ergatomorphism of the males. This specializa- 

 tion is, at any rate, an interesting example of the more advanced 

 state of development of European as compared with North 



