28 Annals of the South African Museum. 



This species is easily distinguished from 0. granifrons, which it 

 resembles, by the smoothness of the ventral surface of the last 

 abdominal and first caudal segment and by the stoutness of the 

 tail. In the male of 0. granifrons the fifth caudal segment is more 

 than 3-J- times as long as broad, and the second caudal segment is 

 considerably narrower than its own length on the upper median 

 line. Further, in 0. granifrons the tarsus of the fourth leg has 110 

 external spine below and only three on the external terminal lobe. 



GEN. PAEABUTHUS Pocock. 



PAKABUTHUS CALVUS, n. sp. 

 Plate IV., fig. 7. 



Male (recently killed, in alcohol). 



Colour ochraceous, the legs and palps paler than the trunk ; the 

 median eye-tubercle blackened. 



Carapace wider than long, much narrowed anteriorly, the anterior 

 width being only one-half the posterior width ; median groove wide, 

 almost smooth, except near the anterior margin of frons, where it is 

 granular ; sides of the carapace with several transverse depressions, 

 which are almost smooth ; median eye-tubercle situated in front of 

 the middle of carapace, quite smooth, as is also a broad band ex- 

 tending 011 each side from this tubercle obliquely forwards nearly as 

 far as the lateral eyes ; rest of the carapace finely granular, the 

 interocular area with coarser granulation ; carapace with a few hairs 

 on anterior edge, but with no trace of hairs or crests on the upper 

 surface. 



Terga. The segments finely granular in the posterior, roughened 

 in the anterior part; the anterior six with a median keel; the seventh 

 with four granular crests, its upper surface smooth at the sides, 

 densely and finely granular (shagreened) on the shallow median 

 depression. 



Sterna smooth and polished, with traces of fine granulation at 

 the extreme lateral borders ; the last segment with four obsolete 

 keels, entirely smooth. 



Cauda very stout, the first three segments of equal width, as 

 wide as the breadth of the carapace across the median eyes, the 

 fourth segment narrower than the preceding ones, the fifth narrower 

 than the fourth ; first two caudal segments flattened above, with a 

 shallow, elongate depression in the middle, which is shagreened in 

 the same manner as that on the last tergal segment, the upper 

 surface at the anterior edge of the depression projecting forwards 



