Species of British Formicidce. 117 



longiusculis ; alis hyalinis, nervis cum stigmate sub-flavescen- 

 tibiis ; nofiis petioli rugosis. 



Operaria. — Testaceo-ferruginea, sparse flavido - pilosula ; capite 

 supra abdoiniiiisque dorso medio et macula ventrali plus miuus- 

 ve fuscescentibus ; scapo basin versus arcuatim flexo ; capite 

 thoraceque longitudinaliter striatim-rugosis; metathoracis spinis 

 binis validiusculis longis ; nodis petioli rugosis. 



Mas. — Nigro-fuscus, nitidus, parcissime tenuiter flavido-pilo- 

 sulus ; mandibulis, articulationibus pedum et tarsis testaceo- 

 pallescentibus ; scapo elongato, fuscescente, abdomine supra 

 obscure rufcscente. 



Myrmica rttginodis, Nyland. Adno. Mon. Form., 929, 2 ; Foers- 



ter, Hym. Stud. Form., p. 66, 36. 

 Myrmica vagmis, Curtis, Trans. Linn. Soc, xxi. 213, 3. 



Female. — Length 2| lines. This sex so very closely resembles 

 that of the preceding, that it is only necessary to point out the 

 distinctions of the present species. The scape is more slender, 

 gradually narrowing to the base, which is bent, but not angulated 

 in front of the arcuation ; the flagellum is also more slender, and 

 the joints rather longer ; the mesothorax is not so deeply rugose- 

 striate,and the thoracic spines are not quite so stout and are more 

 bent inwards towards each other. 



Worker. — Differs from that of the preceding species in the 

 same characteristics as the female. 



Male. — At once distinguished from that of the preceding 

 species by having the antennae rather longer than the thorax, 

 the scape being about one-third of their entire length ; they are 

 usually also paler coloured, and the entire insect is less pilose, 

 particularly the head and legs; the tarsi are more elongate and 

 slender; the metathorax is less deeply notched, and sub-angulated 

 laterally. 



This is in all probability the species described by Linnaeus as 

 Formica rubra, since it usually possesses the character pointed 

 out by the author, " punctum nigrum sub abdomine;" but, as I 

 have observed this character in some examples of other species, 

 I have not thought myself warranted in changing the name : the 

 species is equally abundant with the foregoing, and found in 

 similar situations. 



Mr. Curtis quotes this species as being the Formica uagans of 

 Fabricius, but the description of that author would equally well 



