21 <i Mr. R. I. Pocock on 



Family Hersiliidae. 



Genus HeksiliAj Aud. 



Hersilia sericea, sp. n. (PI, VIII. fig. 9.) 



Colour (in alcohol). Carapace testaceous, clouded with 

 black; clypcus yellow ; mandibles black, with pale transverse 

 median band ; abdomen testaceous, mottled with black, with 

 an irregular median black band anteriorly ; legs yellow, 

 spotted and mottled with black ; distal segment of posterior 

 spinners yellow, with two black spots and black at the apex ; 

 lower side of trunk and limbs yellow. When dry the in- 

 tegument is seen to be covered with silky white hairs. 



Carapace as wide as long, its width about equal to distal 

 protarsal segment of second leg and to patella, tibia, and half 

 the protarsus of the third ; ocular quadrangle longer than 

 wide, a little wider in front. Eyes subequal ; the posterior 

 medians rather less than a diameter apart, the anterior 

 medians a little more than a diameter apart, the anterior and 

 posterior median on each side about a diameter apart ; clypeus 

 exceeding the length of the ocular quadrangle. 



Legs : femora with superior spines black, anterior and 

 posterior spines white; patellar with two superior spines and 

 one posterior ; protarsi Avith a pair of superior spines at the 

 base above and four (rarely three) additional spines, two 

 superior, one anterior, and one posterior ; tibiaj of first and 

 second armed with 8-9 spines. 



Sjminers with distal segment of posterior pair rather short, 

 about as long as tibia of fourth leg, shorter than tibia of 

 first. 



Vulva with lateral portion projecting beyond the median 

 and ending in an inwardly directed spiniforra process. 



Measurements in millimetres. — Total length 8'5 ; length 

 and width of carapace 3 ; length of abdomen 4*5, of posterior 

 spinners 6*2, its distal segment 5 ; length of first leg 24, of 

 second 25, of third 8, of fourth 22*5. 



Loc. Estcourt, 4000 feet {G. A. K. Marshall). 

 Apparently resembling in colour H, albicomis, Simon 

 (Ann. Soc. Ent. France, 1887, p. 273), from Assinie, 

 W. Africa, but certainly differing from it in having the ocular 

 quadrangle wider in front and not perfectly parallel ; nor 

 does the description of the vulva in albicomis apply to that 

 organ in H. sericea. 



It is also closely allied to B. Hildebrandti, Karsch (Zeits. 

 ges. Naturwiss. 1878, p. 312), from Zanzibar ; but without 



