236 BRITISH ANTS. 



ants 6 ; eventually she came to the conclusion that they were not 

 fungoid growths, but probably colonies of an alga. 



I have taken the Acari, Cillibano comata Leon., AntennopJiorus 

 ulhmanni Hall., and Sphaerolaelaps holothyroides Leon., in nests of 

 D. mixto-umbrata. 



Donisthorpea mixta Nyl. 



Formica mixta Nylander Acta. Soc. Sc. Fenn. 2 1050 (1846) 1 ; Schenck 

 Jahrb. Ver. Naturk. Nassau 8 64-66 2 139 3 (1852); Mayr Verb. Zool. Bot. 

 Wien 5 367 (1855) 4 . Formica brunnea F. Smith Trans. Ent. Soc. Lond. 

 (n.s.) 4 1857 278 (1858) 5 : Proc. 88 (1858) 6 : Cat. Brit. Foss. Hym. IP 224 8 

 (1858) : Ent. Ann. 1858 39 9 . Lasius mixtus Mayr Europ. Formicid. 50 

 (1861) 10 . Lasius umbratus r. mixtus Forel Denkschr. Schweiz. Ges. Naturw. 

 26 47 11 216 12 407 13 (1874). Lasius mixtus Er. Andre Spec. Hym. Europe 2 

 196 (1881) 14 ; Bignell Entom. 14 262 (1881) 15 : Young Nat. 3 191 (18S2) 16 ; 

 Dalla Torre Cat. Hym. 7 187 (1893) 17 ; Janet Etudes. Fourmis 13 1-58 

 (1897) 18 . Lasius umbratus race mixtus Grimshaw Ann. Scot. Nat. Hist. 

 1908 89 19 . Lasius mixtus Donisthorpe Ent. Rec. 23 236-238 (191 1) 20 . Lasius 

 umbratus subsp. mixtus Donisthorpe Entom. 44 390 ( 191 1 ) 21 . Lasius umbratus 

 race mixtus Evans Scot. Nat. 1912 106 22 . Lasius mixtus Crawley and Donis- 

 thorpe Int. Ent. Cong. Oxford 1912 2 51 (1913) 23 ; Donisthorpe Rep. Lancs- 

 Chesh. Ent. Soc. 36 1912 40 (1913) 24 : Ent. Rec. 25 64 25 268 26 291 27 (1913). 

 Lasius umbratus subsp. mixtus Hallett Trans. Cardiff Nat. Soc. 45 3 (1913) 28 . 



^ Dirty yellow in colour, being darker, more brownish than umbrata, man- 

 dibles and funiculus of the antennae reddish. The whole body less hairy and 

 pubescent than in umbrata. 



Head scarcely emarginate posteriorly ; eyes small, but a little larger and 

 less flat than in umbrata ; ocelli very small and indistinct ; frontal furrow 

 indistinct ; funiculus of antennae thicker than in umbrata, with joints broader 

 than long. Thorax much less hairy and pubescent than in umbrata. Scale 

 narrowest, and somewhat emarginate at apex, not so high as in umbrata, 

 but higher than in ftava ; gaster with fewer and shorter hairs than in um- 

 brata. Tibiae without outstanding hairs. Long. 3-5-4-5 mm. 



$ Dark brown with mandibles, antennae, and legs reddish ; darker and 

 much less hairy and pubescent than umbrata. 



Head as broad as thorax, but not so large, nor so emarginate posteriorly 

 as in umbrata ; funiculus of antennae thicker than in umbrata with joints 

 not longer than broad. Thorax only slightly narrower than gaster, not so 

 hairy nor so pubescent as in umbrata. Scale not emarginate at apex ; gaster 

 with fewer and shorter hairs than in umbrata. Tibiae without outstanding 

 hairs. Wings infuscate at base, the colour slightly darker and reaching 

 further across, and the discoidal cell smaller than in umbrata. Long. 6.5-8 

 mm. (6-8 mm. teste Andre.) 



<$ Blackish brown, funiculus of antennae and tarsi yellowish ; slightly less 

 robust, a little more shining, and less pubescent than umbrata. 



Head not quite so large as in umbrata ; mandibles armed with five teeth, 

 which are not as distinct as in umbrata ; frontal furrow distinct ; eyes with- 

 out outstanding hairs. Wings as in the female, the colour extending a little 

 further across, and the discoidal cell a little smaller than in umbrata. Long. 

 4-2-4-8 mm. (4-4 J mm. teste Andre.) 



Original description of Formica mixta Nylander [Acta. Soc. Sc. 

 Fenn. 2 1050 (1846)] : 



" Simillima est F. flavae, differt autem : operaria pilis parvis sparsis 

 corporis brevioribus, flagellis antennarum submoniliformibus (h.e. articulis 

 paulo magis discretis), an tennis ipsis, ut videtur, nonnihil majoribus longiori- 



