1900.] Catalogue of the Coleoptem of SouiJi Africa. 465 



■of T. incuUus, the third and fifth rows of tubercles are not 

 carinate as in the hitter, which character is absohitely constant 

 in the fifty odd examples of the South African species I have 

 examined. 



The drawing of the clasps of the penis (plate xxxix., fig. 16) requires 

 some explanation. The outer branch of the forceps curves down- 

 wards, and the median upper lobe, which should l)e a little more 

 acuminate at tip, has a deep, median impressed groove, and on each 

 side of it the two sinuate lines, as seen in the figure, are very sharp, 

 the vertical carina forming a high wall and ending at apex in a 

 sharply hooked tooth. 



Length 14-18 mm. ; width 9-11 mm. 



Hab. Cape Colony (Knysna, Fraserburg, Port Elizabeth, and 

 the whole of the Northern part), Natal (Durban, Maritzburg, Van 

 Reenen's Pass), Transvaal (Pretoria, Rustenburg, Potchefstroom, 

 Lydenburg, Boksburg), Southern Rhodesia (Salislniry, Enkeldoorn, 

 Buluwayo), British Bechuanaland (Kanya), Ovampoland (Okovango 

 River). 



Trox (Omorgus) melancholicus, Fahr., 

 Insect. Caffr., ii., p. 108. 



This species might at first sight be mistaken for small examples of 

 T. incultus. It has been considered as such by Harold, and an 

 examination of Fahroeus' type seemed to me at first to justify Harold 

 in doing so, but after examining the genital organs of one of my co- 

 types, I have come to the conclusion that it is quite a distinct species, 

 and I found also other spjecific characters corroborating this. Thus 

 the size varies very little and is constantly smaller than in T. incultus, 

 the shape and sculpture of the head, prothorax, and elytra are identical, 

 lout the third interval is carinate from the base to past the median 

 part and continued there as elongate, costate tubercles ; those in the 

 intermediate rows are much more distant from each other, and less 

 elongate ; all of them are squamose and the intervals have a row of 

 fairly distinct punctures ; in the genital organs the outer branch of 

 the forceps is declivous, broadly grooved inwardly at the base, the 

 upper median lobe is nearly similar, but the median groove, instead 

 of having a carinate wall running from the base to about two-thirds 

 of the length, is replaced by an auriculate, vertical, arcuate, laminate 

 process not acutely dentate at tip. 



This species seems to be rare ; I have seen only four examples, 

 three of which are females. Not having examined the genital organs 



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