Species of Opisthoplitlialmiis. 177 



a 1 -. Sides of carapace coarsely granular only in the anterior 

 half. Tail long, the width of segment 1 sub-equal to its 

 length along tipper median line . . ? O. pattisoni, n. sp. 



b 1 -. Sides of carapace very coarsely granular as far back as 

 the posterior transverse depressions. Tail stouter and 

 shorter, the width of segment 1 much exceeding its 

 length along upper median line. 



a 1 ^. Inferior median keels obsolete in first caudal seg- 

 ment. Secondary keels on inner part of upper 

 surface of hands obsolete, indicated only by black 

 lines ? 0. chapcri, Sim. 



fe'\ Inferior median ki'els well developed, separated by 

 a distinct groove. Secondary keels of hands dis- 

 tinctly raised ? 0. fossor, Pure. 



b 2 . Sides of the carapace finely granular, the granules near the lateral 

 borders of the interocular area not much coarser than those else- 

 where. 



fl, 14 ? : Hand much depressed, its width not or scarcely exceeding 

 the length of brachium along upper side ; 3 : Length of 

 hand-back considerably exceeding breadth of hand. Ter- 

 minal tooth of superior caudal crests enlarged and spiniform. 



Worcester and Sutherland Divisions 



$ ? 0. austcrus, Karsch. 



b' 4 ? : Hand convex above and very wide, its width much exceeding 

 the length of brachium along upper side ; <? : Length of 

 hand-back less than the breadth of hand in adult. 



a 15 . Tarsi of 4th leg with 3 (very rarely 4) spines on the 

 external terminal lobe and no external spines on the 

 under side ; tarsi of 3rd leg with no (very rarely 1) 

 external spine on the under side and 4 (very rarely 3) 

 on the external terminal lobe ; the superior terminal 

 process of the tarsi very small, much shorter than the 

 lateral lobes. Upper caudal crests with an enlarged 

 terminal tooth in segments '2-4. Little and Great 

 Bushmanland <? ? crassimanus, n. sp. 



i'5. Tarsi of 3rd and 4th legs with 4 spines on the external 

 terminal lobe and 1-3 (sometimes in glabrifrons) 

 external spines on the under side as well, the superior 

 process well developed, as long as the lateral lobes 

 (rarely shorter). Terminal tooth of upper caudal crests 

 not enlarged. 



a 16 . Operculum completely cleft longitudinally and pro- 

 vided with a pair of stylets on upper surface behind. 

 (Males.) 



a 1 ?. Inferior median crests of segments 1 and 2 and 

 often also of segments 3 and 4 of cauda dis- 

 tinctly defined only on the lateral side, the 

 space between them being not grooved but filled 



