SIDUSA. 209. 
Legs brown, i. and ii. darker; tarsus i. yellow. Carapace brown. Cephalic area coloured white or yellow 
(probably white in fresh specimens), owing to an aggregation of cretaceous pigment cells beneath the 
epidermis, its sides deep black ; posterior lateral margin with a patch of white scales or hairs. Apex of 
femur of palpus with a thick tuft of white somewhat clavate hairs. Abdomen dull whity-brown, 
speckled with darker brown, exhibiting on each side of the lanceolate heart-area a row of cretaceous- 
white spots, with a dense central dorsal band of the same in the apical half. Sternum pale yellow and 
ventral area dusky brown. Spinners white, their outer sides suffused with brown. Palpus very 
characteristic, incrassate. Femur strongly curved, with a thick bunch of clavate hairs at its apex above. 
Patella longer than broad, narrower behind, much enlarged on the outer side towards the apex. Tibia 
scarcely longer than broad, narrower behind, with a short, sharp, straight, slender spine at its outer 
apical angle. Tarsus narrow, longer than the tibia; bulb dilate behind on the outer side, with a slender 
spiraloid spine at its apex. 
Hab. Guatemata! (Sarg).—Brazin, Chapada !. 
One cannot doubt that our examples from Guatemala are identical with Peckham’s 
species, though it must be borne in mind that his figure of the tibia of the palpus is 
drawn quite twice longer than broad ; but the description gives it as nearly as wide as 
it is long, thus agreeing with our examples. Peckham has not given any drawing of 
the vulva of the female, which is here figured, so far as I know, for the first time. The 
enamelled covering of scales with the crackled appearance on the cephalic area and 
the abdomen, mentioned by Peckham, lies of course beneath the epidermis and consists 
of aggregations of cretaceous pigment cells; in one example they are entirely absent 
from the abdomen. ‘The males, though somewhat rubbed, present two similar tufts of 
hair about the middle of the cephalic area to those present in S. enermis. ‘The species 
is liable to be confused with Titanattus sevus, Peckh. 
9. Sidusa inermis, sp. n. (Tab. XVI. figg. 3, 3a-c,3; 4,44, 2.) 
Type ¢, gynetype @, in coll. Godman & Salvin. Total length, ¢ 5, 2 6 millim. 
Hab. Mexico, Teapa (H. H. Smith); Costa Rica (Rogers). 
The type-specimen is from Costa Rica. The coloration is almost exactly as in 
S. festiva, except that the femur of leg i. is much darker (in S. festiva it is usually 
yellow, though slightly suffused with brown in some examples). The abdominal 
pattern is less distinct in 8. inermis, but practically the same in both species. The 
best distinctive character will be found in the femur of the palpus, especially when 
seen from the inner side, it being much longer than in S. festive and without the stout 
curved spur at the apex beneath, so conspicuous in that species. Other differential 
characters will be found mentioned in the Table. The male has a conspicuous erect 
tuft of dark hairs just before the middle of the cephalic area on each side. In this 
respect it resembles Titanattus swvus, except that in the latter the tufts are nearer the 
anterior eyes. Superficially, the two spiders look identical, on account of these tufts 
of hair. The female was not detected till after the Table was printed: for the vulva, 
see the Plate. | 
BIOL. CENTR.-AMER., Arachn. Aran., Vol. II., February 1901. 2 et 
