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in the case of Dolerus seems more thau ordinarily capable of leading 

 to false identifications. 



One group of Doleri — that of anthracinus-, Kl., nee Hartig, is 

 distinguished from the other species mainly by a character which has 

 given me a good deal of trouble. Hartig, Zaddach, and Konow all 

 speak of a certain " impression " (Eindruck) on the thorax — Zaddach, 

 in his Latin diagnosis speaks of it as a " fossa " — which in the 

 anthracinus group is said to be " semicircular," and in other groups 

 " angular " (spitzwinklig). This "impression " is said by Zaddach to 

 be at the " apex " of the middle lobes, by Hartig to be at their sides, 

 and by Konow at their " point ^' (spitze). (This latter term being 

 also used by Zaddach in that part of his work which is written in 

 German.) The word " apex " must have been used by Zaddach in its 

 geometrical rather than its zoological sense, for it is the basal end of 

 the middle lobes which is pointed ; and it will have been noticed that 

 Hartig speaks neither of their base nor of their apex, but of their 

 sides. Notwithstanding, I feel sure that all the German authors mean 

 the same thing : viz., that a trench-like impression runs in all cases 

 round the pointed ends of the lobes and a part at least of the sides, 

 and that this impression is pointed at the end in most species, but 

 semicircular in the anthracinus group. But what is this " impression ?" 

 Mr. Cameron seems to identify it with what he terms " the suture 

 bounding the middle lobe of the mesonotum ;" and elsewhere he calls 

 it " the middle suture," and describes the middle lobe itself as 

 U-shaped or V-shaped, according as this " suture " is semicircular or 

 angulated. I find, however, between the middle and side lobes not a 

 suture, but a pair of sutures, which though convergent never meet, so 

 that I cannot recognise in them either a semicircle or an angulation 

 "bounding the middle lobes." Nor does it seem to me that a careful 

 writer like Zaddach could ever have described them as a single 

 " Eindruck ;" much less as a " fossa," for they do not in the least 

 resemble any sort of excavation. Nor, finally, have I ever seen a 

 Dolerus in which the middle lobe itself could correctly be called 

 semicircular or U-shaped. It always ends in what would commonly 

 be called a " point," and is practically V-shaped. 



What I feel sure the German authors mean by their" Eindruck " 

 is not the " sutures," but the whole of a large and really " trench "- 

 like arcuate excavation or depression at the bottom of which they 

 lie. Such an excavation may easily be seen, in a proper light, 

 encircling the "point," and partly also the "sides "of the middle 

 lobe ; and its posterior outline (if that be the proper expression, for 



