1898.] BY MB. C. S. BETTOIS^ IN BRITISH EAST AFRICA. 523 



mandible with two indistinct fuscous stripes above ; abdomen 

 trilineate, each tergite marked with a median spot and a marginal 

 spot on each side, the intervening pale area on each side about 

 twice the width ot the median spot ; palpi with tarsus entirely 

 pale, tibia deep brown, patella paler brown, its distal end and 

 the adjacent end of the tibia narrowly pale ; femur very lightly 

 brownish distally ; 1st and 2nd legs pale, 3rd with femur and 

 patella lightly brownish (legs of 4th pair absent). 



Head-plate and mandible covered with a clothing of short hairs 

 intermixed with a few bristles ; the former a little excelling in 

 width half the length of the tarsus and protarsus of the palp. 



Paljn long, as long as the body and mandibles ; the tibia 

 furnished with long bristles ; the protarsus with five pairs of 

 lougish spines, those at the base of the segment setiform. 



Mandihles elongate ; the upper fang slightly sinuous, lightly 

 concave above, rather strongly convex below, then narrowed at 

 the point ; the teeth arising rather far back, nearly as far back as 

 the base of the flagellum ; the first, second, and fourth long and 

 nearly cylindrical but pointed ; the third minute, lying close to the 

 base of the fourth ; the rest, three in number, forming the outer 

 series, triangular ; the inner basal series also three in number, sharp, 

 the median of the three much the smallest; lower fang long, 

 armed with two strong triangular teeth, and a minute one at the 

 base of the first of these. 



Flagellum membranous, broad, laminate, and incurled at the 

 base, then passing into a slender terminal portion which passes 

 back and rests on the head at the side of the ocular tubercle. 



Measurements in millimetres. — Total length (including mandible) 

 1-5 ; length of mandible 4 ; width of head 3 ; length of palp 15, 

 its tibia 5 ; tarsus and protarsus 5"5. 



Loc. Samburu. 



The absence of the 4th leg makes the generic position of this 

 species a little doubtful. It may perhaps prove to be the male of 

 either B. hrunnipes or B. fuscipes from Somaliland, but is equally 

 likely to be distinct from both. 



Genus Ceroma Karsch. 



CEEOiiA TABiATTJM, sp. n. (Plate XLII. fig. 16.) 



Colour. Head-plate yellowish, irregularly clouded at the sides 

 with brown, pale quite in the middle, tubercle black ; mandibles 

 j^ellow, with two faint brown stripes ; palpi with tibia, protarsus, 

 and tarsus deep brown above, paler below ; abdomen with three 

 black bands, each tergite ornamented with a median and a 

 marginal black spot ; the yellow area on each side about three 

 times the width of the median stripe ; legs yellow, the posterior 

 two pairs hghtly brownish. 



Differing from O.johnstoni, from Nyasaland', in having the 



Pocock, Ann. Mag. Nat. Hist. (6) sx. p. 253 (1897). 



