MACROTHELE.—PACHYLOSCELIS. 93 
The mate is of a rather clearer and lighter colour than the female, especially the legs and palpi; the abdomen, 
however, is as dark, and the oblique lines on it are more distinct ; the tibie of the first pair of legs are 
very strong, and at their extremity on the outer side, somewht underneath, is a strong obtuse prominence 
whose extremity is armed with eight or nine short, strong, divergent spines; the metatarsi of the same 
pair are bent, and have a conical tooth-like prominence near the middle on the outer side. 
The palpi are strong, the radial joint somewhat tumid; the digital joint small, but with its outer extremity 
produced into a long, cylindrical, finger-like projection, armed with several short black spines at and near 
its termination. The palpal organs consist of a small roundish-oval bulb, gradually produced into a long 
curved spine, with a fine hair-like termination. 
Hab. Guatemaua, Cubilguitz, Chamiquin, Tucuru, Escuintla (Sarg). 
Mr. Sarg says of this spider that it lives in holes in the ground, near which it makes 
small, strong, irregular webs, consisting of various floors or chambers. It is a very 
remarkable species, from the peculiar form of the digital joint of the male palpus, and 
is, so far as I am aware, the second species only of this genus recorded as yet from the 
New World. 
PACHYLOSCELIS, Lucas. 
Pachyloscelis robustus, sp. n. 
Adult female, length 104 lines; to end of faices 13 lines. 
The cephalothorax, falces, legs, palpi, and other fore parts are of a rich dark brown colour ; in some examples 
the genua, tibis, metatarsi, and tarsi of the two anterior pairs of legs, and occasionally of all the legs, 
are of a reddish-yellow-brown hue. The abdomen is of a dull but warm brown colour. 
The cephalothorax is slightly longer than broad ; broadest between the insertion of the first and second pairs of 
legs, and thence narrowing gradually to the hinder extremity. Its surface is very glossy and smooth. 
The caput is considerably elevated, the hinder part abrupt and rounded, broad and truncated in front ; 
the thoracic indentation is large, deep, strongly curved, the convexity of the curve directed backwards, 
and at each of its ends is an additional indentation. The thorax is flat, and has a strong depression at 
the thoracic junction. The height of the clypeus is about equal to the length of a line formed by the 
fore central pair of eyes. 
The eyes are eight in number, seated on very slight tubercles, unequal in size, and form a transverse oblong 
rectangular figure about two and a half times longer (in its transverse diameter) than broad, ‘They may, 
however, be most conveniently described as in three groups rather widely separated from each other—a 
central group of two (the smallest) near together in a transverse line, and at some distance on each side a 
group of three in a triungle formed by the lateral pair and the hind central eye next to it. The hind 
central eyes are oval and not much, if at all, larger than the fore centrals, and each is separated from the 
hind lateral eye next to it by about its own diameter’s distance. The fore laterals are slightly the largest 
(though in some examples the hind laterals appear the largest), aud are separated trom the hind laterals 
by a space equalling about once and a half their diameter. The interval between the eyes of the central 
group is about a diameter, and each is separated from the fore lateral on its side by about three diameters 
of the latter. 
Legs very short, strong, 4, 3,1, 2; those of the two hinder pairs considerably the strongest, furnished sparingly 
with hairs and bristles ; the edges of the undersides of the tarsi and metatarsi of the first two pairs are 
furnished with short strong spines, and on the upperside of the metatarsi of the third pair are two 
parallel rows of spines. The outer sides of the genua of the fourth pair are thickly covered with very 
short denticular spines, a few similar ones are also on those of the third pair, with a marginal row of the 
same at the fore extremity, both of the genua and tibia. Each tarsus ends with three strongly curved, 
simple claws, beneath which is a small group of bristles, though scarcely to be called either a scopula or 
claw-tuft. 
