Powzrr.—Oa Desis robsoni. 265 
Falees a rich red brown, glabrous above, hairy beneath, inner and 
upper border fringed with long coarse dark hairs. Fangs very dark red 
brown, nearly black proximally. 
Sternum yellowish brown, with a dark edge, clothed with yellowish 
white hairs. 
Lip and maxille reddish brown, both with a pale border anteriorly, 
clothed with yellowish white hairs, inner border of maxille fringed with 
long coarse dark hairs. 
Abdomen greenish grey, in some specimens yellowish grey, paler beneath, 
thickly elothed with yellowish white and dark hairs intermixed. 
Coxal joints of legs yellowish brown. Legs otherwise same colour as 
abdomen but yellower, anterior pair inclining to brown, in some specimens 
much browner than in others. 
Palpi yellowish brown. 
Cephalothorax nearly one and two-thirds longer than broad, sides nearly 
parallel, scarcely contracted anteriorly, and cut off nearly square, sides of 
thorax only slightly rounded; longitudinally a very flat uniform convexity 
above, becoming somewhat more abrupt anteriorly, transversely only 
moderately convex. Normal grooves of thorax feebly indicated by darkish 
lines. A short deep median groove to thorax. 
Mandibles equalling the cephalothorax in length, directed nearly straight 
forwards, cylindroid and robust, immediately beyond their origin on upper 
and outer side is a small prominent ovoid boss. 
Upper border of groove for fang, armed with six teeth, the first small 
and rather remote from extremity, the second the largest of all, the other 
four smaller and regularly diminishing. Lower border armed with two 
teeth, the first close to the insertion of the fang, moderately large, the 
second quite small and on a level with the first of the upper border. 
Fang long, rather straight. Eyes of very uniform size, the posterior middle 
pair being the smallest; disposed in two rows, the anterior straight or 
curved very slightly indeed, the opening of the curve being forward. The 
posterior. row nearly straight, but in consequence of the small size of the 
middle pair a line touching their posterior margins would be slightly concave 
backwards. 
Anterior middles less than own breadth from border of face, lateral 
middles almost on border. Anterior middles separated from one another 
by own diameter, and from laterals by more than twice own diameter. 
Posterior middles more than own distance from anterior middles and nearly 
four times own diameter apart, the same distance from posterior laterals. - 
Lateral eyes barely their own diameter apart. Anterior middles situa 
on a slight common eminence, they look directly forwards; anterior laterals 
a4 
