Royal Physical Society. 117 



of the elytra, nearly half as broad as long, somewhat convex, 

 the sides moderately strongly rounded (exactly as in tristis), 

 more narrowed behind than in front, so that the greatest 

 breadth is before the middle. The posterior angles are right- 

 angled, the posterior margin feebly sinuated on each side in 

 front of the scutellum. It is covered with a dense yellow pubes- 

 cence as in tristis, but is not granulated like it, but covered 

 with shallow punctures, so that under a strong lens it looks 

 exactly as if pitted with the small-pox, and out of each shallow 

 flat pit issues a yellow hair (sometimes two, springing from the 

 same centre) ; these pits are arranged in a sort of irregular 

 transverse order (see fig. 20), which gives 

 the thorax to the naked eye the ap- lo * 



pearance of being strongly transversely 

 wrinkled. The elytra are densely and 

 finely punctate, with indistinct, very eva- 

 nescent traces (when highly magnified) 

 of similar depressions being scattered 

 over them, and with indistinct traces of 



striae at the apex ; they are clothed with a purplish brownish 

 bloom similar to that of tristis, and with yellowish hairs princi- 

 pally seen at the base. The legs are brownish red, feet lighter. 

 Till this species was made known by M. Kraatz, it had been 

 always overlooked. On a hasty glance it looks exactly like tristis ; 

 a little better inspection, particularly of the apparent granu« 

 lations on the thorax, leads one to suppose it is rotundicollis, but 

 a careful examination brings out the much deeper and differ- 

 ently formed punctuation of the thorax. This is the only cha- 

 racter to be relied on to separate it from tristis ; for although the 

 antennse are not so abruptly or heavily clavate as in that species, 

 and are entirely of a reddish brown instead of having a blackish 

 club, still in neither particular are they so different as to be beyond 

 similar variations to be found in the true tristis. I therefore 

 felt great difficulty in making up my mind whether they were 

 distinct species or not. Thanks to the liberality of M. Kraatz, 

 who supplied me with specimens of his neglectus, I was enabled 

 to examine them all very carefully, which I did under high 

 powers of the compound microscope, and although there is in 

 one sense undoubtedly a transition between tristis and neglectus 

 through rotundicollis, inasmuch as while the sculpture of the 

 thorax in tristis is slightly wrinkled, that of rotundicollis is gra- 

 nulated, and that of neglectus variolose, still there did appear a 

 greater difference between neglectus and rotundicollis than be- 

 tween the latter and tristis. It is not easy to embody the dif- 

 ference in words, but I am enabled by the kind assistance of 



