Mr. A. MuiTay's Monograph of the genus Catops. 143 



the sides, broadest in the middle; nevertheless only a little 

 narrowed in front and behind, in front rather narrower than 

 behind ; the posterior angles sometimes a little pointed *, 

 the posterior margin straightly truncate, and only towards the 

 middle very slightly sinuated. It is covered with a yellow silken 

 pidjescence. The elytra, as well as the whole body, are black ; 

 they have a brownish-blue or purplish peachy bloom, with a 

 yellowish pubescence more conspicuous at their base and basal 

 margins than on the disk. They are finely punctured, very im- 

 perceptibly striated, longish oval, in the middle a little widened, 

 behind obtusely acuminate. The legs are ferruginous red, the 

 posterior thighs sometimes brownish. 



This is the first of a little group of species, which, with a de- 

 cided yellow pubescence on the thorax, has a brownish-blue or 

 purplish bloom on the elytra, accompanied with yellow hairs or 

 ])ubescence conspicuous along the base and basal margins of the 

 elytra, — a character which will limit our comparison to only two 

 or three species. The two species just described, C. coracinus 

 and C. morio, have also yellow pubescence on the thorax, but 

 their elytra have not a purplish bloom, but a greyish- ash bloom, 

 and want the yellow hairs along the base. The yellow pubes- 

 cence on the thorax of these two also is feeble both in colour and 

 consistence compared with those which follow. The form of 

 the thorax of this species distinguishes it from all pjo-. 13. 

 the others. Figure 13 shows the relative form 

 of the thorax of nigrita and tristis, the plain line 

 being the outline of iiigrita, and the dotted line 

 that of tristis. These two species are in other 

 respects extremely alike. The antenna? however 

 also furnish characters of discrimination — the 

 club of tristis being heavy and thick, while the antennscofmV/nVa 

 arc only obsoletcly clubbed. The great breadth of the thorax of 

 grandicollis, Erichs., easily distinguishes it ; and the form of the 

 thorax of rotundicollis, Kelln., which is an exaggerated form of 

 that of tristis as above delineated (fig. 13), will prevent nigrita 

 being confounded with that s))ecies. The elytra in both nigrita 

 and tristis are elongate and give a long character to the whole 

 insect, while rotundicollis has the elytra short and rapidly acu- 

 minate. 



* Erichson in his description states that tlie posterior angles arc pointc<l, 

 but Kraatz says that he cannot agree with liim in that respect : — " accord- 

 ing to my view," he says, "they are right-angled, in not a few exani])k's 

 ])assing into obtuse-angled." I have examined a considerable scries 

 carefully with a view to determine this point, and find that both are 

 right. I possess specimens which have the posterior angles pointed, and 

 others where there is no appearance of a point, but the line of the base of 

 the thorax perfectly straight. This is another proof of the variable cha- 

 racter of the genus. It also shows us how inade(jnate are Spence's sec- 

 tional divisions which are founded on this verv character. 



