1898.] BT MR. C. S. BBTTON IK BRITISH EAST AFRICA. 5l7 



of 1st leg and a little longer thau patella, tibia, and half protarsus of 

 4th, longer than protarsus and tarsus of 1st, than tibia, protarsus, 

 and tarsus of 2nd, and than patella, tibia, protarsus, and tarsus of 

 3rd, and just about equal to tibia, protarsus, and tarsus of 4th; 

 width of cephalic region exceeding length of 1st protarsus and 

 just about equal to tarsus and protarsus of 4th. 



Vulva as in figure. 



Measurements in millimetres. — Total length 15 ; length of cara- 

 pace 7-3 ; width of head 4-3 ; length of 1st leg 16, of 2nd 12, 

 of 3rd 10, of 4th 14-5. 



Loc. Mbuyuni. A single adult female. 



Evidently nearly related to Stegodyplius africanus of Blackwall 

 from the Zambesi region (Ann. Mag. Nat. Hist. (3) xviii, p. 453, 

 1866), but apparently differing in having the hairs on the upper half 

 of the mandible white instead of reddish yellow, in the presence 

 of the narrow dark transverse line on the face, and in the absence 

 of a dark sinuous stripe on each side of the middle line of the 

 dorsal side of the abdomen. From S. mimosanan Pavesi (Ann. 

 Mus. Genova, xx. p. 81, 18S4), from Shoa, lineifrons also differs in 

 the absence of the abdominal bands and the presence of the facial 

 line, and also apparently in the coloration of the 2nd leg. 



Stegodyphus bettoni, sp. n. 



Colour. Carapace clothed with black hair, with a mai'ginal 

 border of white hairs extending from the antero-lateral eye, and a 

 wide white, irregularly oblong, patch occupying the upper and 

 posterior portion of the cephalic region, and breaking up in front 

 into narrow stripes, of which one on each side extends forwards 

 as far as the posterior median eye ; mandibles black, their basal 

 half marked with a transverse white stripe, separated by a space 

 about equalling its own width from the edge of the clypeus : legs 

 variegated with incomplete rings of brown and white ; femora of 

 1st and 2nd blacker, with snow-white patches : abdomen testaceous, 

 covered above with yellow hairs, without clearly defined longitudinal 

 black bands ; black below, and variegated with white patches. 



Length and width of carapace as compared with legs almost the 

 same as in the preceding species, the legs being slightly longer. 



Measurements in millimetres. — Total length 11; length of cara- 

 pace 4 ; width of head 2-3 ; length of 1st leg 8-5, of 2nd 6-5, 

 of 3rd 5-1, of 4th 8, 



Loc. Samburu. 



Although the single example of this species that was obtained 

 is an immature female, 1 have not hesitated to describe it, the 

 females of this genus being generally readily recognizable by colour- 

 characters ; and since these characters are not, within my experience, 

 subject to much variation with growth, there is no reason for 

 supposing that the adults will differ from the immature type 

 specimen of the species in any important character but size. 



8. bettoni may apparently be recognized from the rest of the 

 known tropical African species by the colouring of the carapace 

 and mandibles. 



