Species of Opisthophthalmus. 147 



encircling the hair-pits. The presence of these granules and of those 

 on the upper crest of the brachium constitute the principal characters 

 by which this species can be distinguished from the closely allied 

 0. capensis. Length of the carapace in adult $ 12f-15 mm. ; in 

 adult $ 13-14^ mm . 



OPISTHOPHTHALMUS CAPENSIS (Herbst). 



In his ' Revision der Skorpione ' (p. 100) Kraepelin appears to 

 have confused two different species under the name of 0. pilosus. 

 The male is, of course, that of capensis, and it seems to me very 

 probable that the female of his pilosus is the male of 0. granifrons, 

 Pocock. I have not seen 0. latro, Thor., but it is evidently only a 

 male specimen of capensis, which is larger and darker than usual. 

 In Thorell's elaborate description I cannot discover a single structural 

 difference, and Thorell himself relied only upon the larger size and 

 dark coloration to distinguish his species from capensis. A very 

 large male of the latter in our collection measures 83 mm. in length, 

 while Thorell's latro is 89 mm. long. In the structure of the finger- 

 keel and of the superior crest and posterior surface of the brachium, 

 in which capensis differs from its nearest allies, leipoldti and 

 f/ranifrons, latro resembles capensis. Further, latro, Thor., and 

 pilosus, C. L. Koch, are stated to be identical by Kraepelin, who 

 was able to examine and compare the type-specimens of both. 



In a previous paper (p. 20 of this journal) I described a scorpion 

 from the Tulbagh Division, under the name of 0. fuscipes. At that 

 time I was acquainted only with the form of 0. capensis which occurs 

 in the Cape Peninsula, and was able to sharply separate it from 0. 

 fuscipes, relying principally on the shape of the spiracles, the 

 number of spines on the external lobe of the posterior tarsus, and 

 the coloration. An examination of a number of additional specimens 

 of both forms, especially those taken at new localities, has convinced 

 me of the trifling specific value of these characters in the present 

 case. Thus the external lobe of the fourth tarsus is always provided 

 with 3 spines in specimens of either form taken outside of the 

 Cape Peninsula ; in specimens of capensis from Stellenbosch and 

 Malmesbury the spiracles are often (and in the specimens from 

 the Peninsula occasionally) wider in the middle than at the ends, 

 thus approaching the condition which obtains in fuscipes. Moreover, 

 in specimens from the Paaii, which otherwise closely agree with 

 fuscipes, the spiracles although wider in the middle are generally 

 narrower than in the typical fuscipes, the narrowest spiracles of these 

 specimens exactly resembling the widest spiracles of the Stellenbosch 



11 



