30 Annals of the South African Museum. 



The sex of this specimen is beyond doubt, as the usual pair of 

 chitinous stylets, characteristic of the male, is present, attached to 

 the soft skin at the posterior end of the genital orifice. This species 

 is well characterised by the smoothness and the remarkable thick- 

 ness of the cauda. It comes nearest to P. planicauda, Pocock, the 

 female and male of which have similar palps,* although the movable 

 finger in the latter species is shorter in proportion to the length of 

 the hand-back. The shagreened part of the caudal segments is also 

 similar in both species. The lobe-like basal angle of the scape of 

 the pectines is peculiar, exactly resembling that occurring in the 

 female of planicauda. 



Synopsis of the Species of OPISTHOPHTHALMUS 



in the collection of the South African Museum, which have the median groove of 

 the carapace distinctly forked in front and the eye-tubercle situated far behind 

 the middle of the carapace. f 



a. Under side of the first 4 caudal segments convex, not grooved longitudinally, 

 with the median crests quite obsolete, represented at most by black lines. 

 (The superior process of the tarsi much shorter than the lateral lobes.) 



a 1 . External lobe of tarsus of 4th leg with 3 spines; interocular area of cara- 

 pace nearly smooth, the granules bordering it only slightly coarser than 

 the rest. Little Bushmanland <? ? 0. schlccJitcri, n. sp. 



ft 1 . External lobe of tarsus of 4th leg with 4 spines ; interocular area granular 

 on the anterior half, bordered on each side by a strip of coarser granules. 



-. Entirely black ; lower surface of abdomen and of first 3 caudal segments 

 smooth and polished, that of 4th caudal segment somewhat roughened ; 

 terminal tarsus of 4th leg with 1 external spine below. Namaqua- 

 land, C. C f 0. atcr, n. sp. 



b-. Ochraceous to brown, the abdomen darker ; lower surface of last 

 abdominal and of first 4 caudal segments densely and finely granular 

 in the <? , smooth in the ? , except in the 3rd and 4th caudal segments, 

 which are also thickly granular ; terminal tarsus of 4th leg with no 

 external spine below. Naniaqualand, C. C. <? ? O. granicauda, n. sp. 



b. Under side of the 4th caudal segment with distinct median and lateral keels, 

 the surface distinctly grooved between the keels. 



ft3. Last segment of the sterna always coarsely, though often somewhat 

 weakly granular, at least in the middle ; terminal tarsus of 4th leg 



* The specimens described by Pocock (Ann. Mag. N. H. (6), vol. in., 1889, p. 345) 

 as the male of planicauda belong to another species. 



t O.fossor with occasionally partially developed fork, 0. intcrmcdius, Kraepelin, 

 with incompletely developed fork, and 0. latro, Thor. (the last two being unknown 

 to me), are the only species omitted, which may possibly be brought into this 

 category. 



