MESOPNEUSTES .—ITYS. 127 
colour is jet-black, with a transverse whitish line on the middle of the underside, indicating the unusual 
position of the ordinary spiracular openings. It is furnished with numerous long, strong, bristly hairs. 
Hab. Mexico, Teapa in Tabasco (H. H. Smith). 
ITYS, gen. nov. (Theridiide). 
Cephalothorax oval, broad and bluff in front; the lateral constrictions at the caput very slight; caput and 
thorax (in profile) on one level, the hinder slope very gradual, the profile line of the caput running on a 
slight slope to the fore-central eyes ; the normal lateral indentations between the caput and thorax broad 
and shallow ; the height of the clypeus equal to half that of the facial space. 
Eyes small, subequal, occupying the whole width of the anterior portion of the caput; looked at from in front 
the anterior or lower row is straight, the posterior longest and much curved. The intervals between those 
of the posterior row are equal. Those of the fore-central pair smallest, dark-coloured (the rest being 
pearly white), and near together, but not quite contiguous, with perhaps half a diameter’s interval between 
them. Those of each lateral pair contiguous to each other, and obliquely placed on a slight tubercle. 
Legs moderately long, slender, 1, 4, 2,3, furnished with hairs, and a single slender spine on each of the genual 
and tibial joints. 
Falces small, straight, and considerably inclined towards the maxillee. 
Maville strong, especially at the base, not very long, inclined to the labium, which is short, small, and some- 
what semicircular in form. 
Sternum broad, heart-shaped, and rather prolonged at its hinder extremity into an obtuse point between the 
coxee of the fourth pair of legs. 
Abdomen oval, subcylindric in form. 
This genus belongs to the subfamily Erigonini, Sim., but it cannot be considered 
equivalent to any of the numerous genera into which the European species of that sub- 
family are now subdivided. 
Itys pergrata, sp. n. 
Adult male, length 1 line. 
Cephalothorax dull orange-coloured, a little suffused on the sides with brownish. The ocular area, and also a 
small space behind it, is furnished with prominent coarse hairs. 
The eyes are on black spots ; the four centrals form a trapezoid, whose length and breadth behind are equal, 
but its anterior side is much shorter. The clypeus is nearly vertical. 
The legs are bright yellow. 
The palpi are short, similar to the legs in colour. The cubital joint is small and short, the radial joint is 
scarcely longer but much stronger, and has an angular prominence at its fore extremity a little on the 
outer side. The digital joint is large. The palpal organs are highly developed, prominent, complex, with 
a semicircular or crescent-shaped process at their base on the outer side, and a long, strong, duplex, 
coiled, sharp-pointed spine, which issues from their outer side, passes over the middle, and encircling their 
extremity ends in a strongly sinuous coil. 
The falces, maxille, labium, and sternum are similar in colour to the cephalothorax. 
The abdomen is of a pale drab-yellow colour, with a black longitudinal central stripe on the fore-half of the 
upperside, with a small prominent point on each side near the middle and at the posterior extremity, 
followed by two (perhaps in some examples more) angular black bars or chevrons, whose angles and ends 
are dilated into blotches; on each side of the anterior part there is also a short longitudinal black bar or 
stripe. The spinners are small, compact, those of the inferior pair longest and strongest, and encircled at 
the base with a black bar. 
Hab. Guaremata. Coban (Sarg). 
This spider bears some resemblance to the genus Japinocyba, Sim., and the late 
