134 the entomologist's record. 



Messrs. Beare and Donisthorpe's catalogue, the authors pointed out 

 (Ent. Rec, xvi., p. 290) that we do not possess G. nannetensis, Mars., 

 as British, and G. punctulatus, Th., and G. rotundatus, Kug., are 

 synonymous. 



When examining my series of Gnathoneus last year, most of 

 which I had taken in old birds' nests, I came to the conclusion that 

 there were two distinct forms, one a shining diffusely punctured insect 

 with large teeth to the front tibiae, the other having very closely 

 punctured and dull elytra, and small anterior tibial teeth. I then 

 looked at the labels of each specimen and was somewhat surprised and 

 much gratified to find that, without one exception, all the specimens 

 of the first form were found in carcases, and all those of the second 

 in birds' nests, so that I had here a third specific distinction between 

 the two forms. Mr. Donisthorpe has kindly supplied me with Mr. 

 Lewis' lengthy synonymy of G. rotundatus, Kug., but I am afraid I 

 have been able to make little of it. I should, however, have no doubt 

 that the type G. rotundatus is the carrion-feeding species. Whether 

 the other species has already been described I cannot ascertain for 

 certain, but rather than leave the whole matter unpublished any longer 

 I have thought it best to point out its specific characters, and give it a 

 name, G. nidicola, which, however, can be easily sunk in favour of an 

 older name if necessary. The following is a description of the species: 



Black or pitch-black, extreme apex of elytra sometimes rufescent; head closely 

 punctured, frontal stria wanting; antennae reddish; thorax somewhat diffusely 

 punctured, more thickly at sides; elytra with stria as in G. rotundatus, Kug., 

 diffusely punctured at base, very thickly punctured towards apex, the punctures 

 running together into rows in the apical third, so that this part appears dull and 

 very finely striated longitudinally ; anterior tibia 1 distinctly dilated, with nine to 

 ten small teeth, the spaces between them very slightly convex, or flat; the apical 

 tooth and the next towards the base are separated by a distinctly longer interval 

 than the others ; intermediate tibias slightly dilated. 



In G. rotundatus the front tibias are distinctly narrower than in G. 

 nidicola, and possess large teeth with well-marked, strongly concave, 

 intervals, very different from the small teeth and flat intervals of the 

 above species. The intermediate tibiae are less dilated and have 

 conspicuously longer teeth. G. rotundatus has the apex of the elytra 

 shining and diffusely punctured. It also seems to be more variable in 

 size, at least, I have not seen any specimens of G. nidicola nearly as 

 small as the smallest G. rotundatus. The following table will serve to 

 distinguish the two species : 



Anterior tibias narrower, with large teeth and convex intervals ; 



apex of elytra shining, diffusely punctured; habitat, carrion. G. rotundatus. 

 Anterior tibiaa broader, with small teeth and almost flat intervals ; 



apex of elytra dull, closely punctured; habitat, birds' nests. G. nidicola. 



I have examined quite fifty specimens of both species and have not 

 come across one that has one of the two structural characters without 

 the other, indeed, I have seldom hesitated a moment before deciding to 

 which species any individual specimen belongs. 



With regard to the difference of habitat being a distinction of 

 importance, this is most strikingly illustrated in the specimens I took 

 last year. Out of about thirty specimens of Gnathoneus, only two are 

 G. rotundatus, one of which was taken in carrion, the other in rotting 

 vegetable matter, whereas all the rest were taken in birds' nests. I am 

 quite aware there are many " collectors " who do not regard this last 



