PCCILAMA. 571 
transversely, than broad ; the first two ventral opisthosomatic segments are not longer 
than the width between the spiracles. The mandibles, as in many members of the 
genus Hrginus, are very much developed. 
A single species only occurs in the collection, and its characters are described 
below. 
1. Pecilema rastellifera, sp. n. (Tab. LIII. figg. 17, 17 a, }, 3.) 
Type, d, in coll. Godman & Salvin. Total length 8 millim. (excl. mand.). 
3. Hye-tumulus low, three times longer, transversely, than broad, plain, without warts or spines. Tergal 
scutum without well-marked transverse segmental strie, but with vestigial grooves, sufficient to suggest 
the original segmentation; the third segment bearing a pair of short cusps transversely situated in the 
middle. Tarsi i. and ii. with one claw; iii. and iv. with two claws. Tarsal segments, i. 8, none dilate, 
1 and 8 being twice as long as the rest; ii, (absent); iii. 9; iv. 11. 
Coxa of palpus with along inferior apical denticle and two smaller ones ; femur dilate, compressed, excavate on 
the inner side, with ten small dorsal tubercles and eight longer ventral denticles, with four other smaller 
ones at the basal end of the series; patella subcylindrical, apically dilate, its inner margin carinate, 
bearing a few short fine spines; tibia broad, oval-elongate, compressed, excavate beneath, bilaterally 
dilate, forming a thick lamelliform plate, its margins bearing numerous short fine spines, becoming 
stouter towards the apex; tarsus narrow, cylindrical, excavate beneath, marginally set with a series of 
short fine spines on each side, terminating in a single stout claw, slightly more than half the length of 
the segment. 
Mandible: basal segment globular above, set with a short series of denticles on its lower outer margin, and a 
cluster of from 16—20 tubercles on its upper outer margin, besides others on the posterior, inner, and 
anterior margins. Apical segment dilate, gibbous above, the movable digit being half the total length of 
segment, bearing a single, large, broad tooth towards the base ; the fixed digit bearing anteriorly a finely 
serrated carina. 
Legs: coxa i. with a curving row of tubercles beneath, absent from ii., iii., and iv.; coxa iv. with a short, 
depressed, superior, apical marginal spur. Trochanter iii. with a small, iv. with a longer, stouter, curved, 
though comparatively short, posterior apical tooth. 
Femora i. and ii. with rows of fine cuspules on all sides; iii. with similar rows of larger cuspules, the apical 
four or five of the infero-posterior and anterior rows being longer than the rest. Femur iv. curved, 
strongly dilate on the apical half, bearing an inner series of 10 or 11 long teeth, the basal three longer 
and wider apart, longer than the greatest diameter of the segment; a dorsal series of 18—20 tubercles, 
forming a serratiform ridge, and an external apical serratiform series of 7-8 denticles, the distal tooth 
being strongly curved towards the patella. Patelle i., ii., and iii. simple, ili. enlarged; iv. also enlarged, 
apically furnished with numerous dentiform tubercles, three longer and more conspicuous on the inner 
inferior margin. Tibise i. somewhat dilate ; ii. narrower; iii. enlarged, with tubercles more conspicuous ; 
iv. with several series of more or less conspicuous dentiform tubercles beneath. The edges of the sternal 
segments iv.—vii. set with a row of small tubercles. 
Hab. Mexico, Chiapas (Sarg). 
The following five genera, three of them new, are so closely allied to Hrginus, and 
yet quite distinct, that it is necessary to call attention to them. ‘Their essential 
characters are given in the Table, anted, p. 550. A short description of the . type- 
species of each of the new genera is added :— 
Apt 2 
