214 ADEPHAGA. [Gijrinvs. 



G. bicolor, Payk. Very like the preceding but more elongate, and 

 on an average larger, with the sides more parallel, and the elytra longer 

 with their apices more rounded, so that the external angle is not marked ; 

 according to ]\I. Bedel the mesosternum is always black in this species 

 and red in G. distinctus, but this appears to be a variable character, and 

 cannot be relied on. Long. 6-7^, lat. 2^-3^ mm. 



Rare ; most of the specimens standing under this name in our collections belons: to 

 the preceding species ; it has been taken in Durham, and also at Horning Fen; it has 

 also been recoi'ded from Swansea, Exniouth, Weymouth, Graveseud and Liverpool, 

 but all these localities are doubtful ; in a long series of O. distinctus so many varia- 

 tions occur that it is probable that this species may be only an extreme variety of 

 that insect, although in itself it seems very distinct by reason of its elongate and 

 laterally 'compressed form ; specimens, however, of undoubted G. distinctus occur 

 which present this same peculiarity of form, although as a rule that species appears to 

 be more oval and less elongate than G. hicolor. 



G-. colymbus, Er. {G. caspim, Men., 1833, Cat. rais. p. 142 ; Aube, 

 Icon. V. p. 3S6, pi. 44, spec. p. 679 ; distinctus, Aube, Icon. v. p. 385, 

 pi. 43, spec. p. 366 ; colymhiis, Er., 1837, Kaf. Mark. i. p. 191 ; lihanus, 

 Aube, 1838, spec. p. 667). 



As there is so much confusion over 'this species, and as in the latest 

 European catalogue (Heyden-Reitter-Weise, p. 32, 1883) G. caspi'us, 

 Men., and G. colymbus, Er., are given as separate species, although in- 

 cluded together, as in the above synonymy, by M. Regimbart in his 

 monograph of the same date (1883), I have thought it best to give a 

 translation of liis description : — 



"A very variable species, of rather long oval shape, never parallel, 

 generally a little contracted behind ; upper surface shining, black, with 

 bluish, or sometimes slightly greenish reflections, broadly and strongly 

 bronzed on the sides ; underside black, with the mesosternum and the 

 anal segment obscurely ferruginous, often almost black. Elytra covered 

 with a rather fine punctuation, sometimes thick and rather strongly 

 impressed, sometimes more diffuse and obsolete ; sometimes even the 

 points take the form of very short transverse striolte ; these variations 

 in the punctuation are independent of sex and locality. The truncation 

 of the apex of elytra is a little oblique and slightly rounded, with the 

 external angle obtuse and more or less roiinded, and the internal almost 

 a right angle narrowly rounded ; the punctures of the series on the elytra 

 are rather dull, rarely of a moderate size, set somewhat widely apart, and 

 rather stronger externally ; the border is narrow and terminated a little 

 behind the external angle." Long. 5|-7, lat. 3-4 mm. 



The descriptions of G. colymhus and G. caspius as given by most 

 authors in many points so closely resemble one another that it is no 

 wonder that a confusion has arisen ; there seem, however, to be three 

 forms, one with the interstices smooth, the second with the interstices 

 plainly punctured if magnified, and the third with the interstices covered 

 with distinct and rather strong transverse striae. Aube distinctly says 

 of his cas'pius that it has the interstices smooth, and Kiesenwetter (Insect. 



