SIDUSA. 213 
figure (fig. 6 6) exhibiting what I believe to be the vulva of the immature female may possibly represent 
that of a distinct, though exceedingly closely allied, species. 
Hab. Mexico, Omilteme, Orizaba (H. H. Smith); Guatemata (Sarg). 
It can be recognized by its excavate mandibles and brown mottled colour. See 
Table of species. 
12. Sidusa vittata, sp.n. (Tab. XVI. figg. 7, 7a, 6, 2.) 
Type, 2, in coll. Godman & Salvin. Total length 6 millim. 
Carapace brown, cephalic area darker, more or less clothed with white hairs, no marginal white band. Legs 
yellow, the apex of the segments slightly suffused with dusky brown. Abdomen pale, more or less 
distinctly mottled with black streaks and spots; there is a more conspicuous, but small, recurved 
horseshoe-shaped dorsal dark mark anteriorly, a central broad /“\-shaped black slender mark about the 
middle, followed, just above the spinners, by a small but distinct black wedge-shaped mark. Ventral 
and lateral areas pale and speckled with sooty-black. In some examples these marks are almost obliterated. 
Vulva variable, according to the amount and disposition of the pigment present: see Plate. Tibia i. with 
lateral spines inside ; protarsus i. without any lateral spines; tibiee iii. and iv. with a dorsal basal spine. 
Hab, Guatemaua (Sarg). 
13. Sidusa nigrina, sp.n. (Tab. XVI. figg. 8, 8 a—c, 2.) 
Type, 2, in coll. Godman & Salvin. Total length 6 millim. 
Carapace yellow or orange, with the cephalic area entirely black. Legs wholly yellow. Abdomen dull white, 
with a large, more or less distinct, black, piriform dorsal patch, narrowing somewhat abruptly to the 
spinners; lower lateral area streaked and spotted with black; ventral area dull white, with or without 
one or more broken dusky lines. 
Tibia i. with lateral spines on the inside; protarsus i. without any lateral spines; tibie iii. and iv. with small 
dorsal basal spines. Vulval area obtuse triangular, with a pair of black orifices anteriorly, more or less 
definitely connected with curving sinuous internal ducts (see Plate). 
Hab. Mexico, Omilteme in Guerrero (H. H. Smith). 
14. Sidusa albida, sp. n. (Tab. XVI. fig. 9, 2.) 
Type, @, in coll. Godman & Salvin. Total length 5 millim. 
General appearance very much as in S. vittata, but the abdomen is dorsally almost entirely dark black-brown, 
with a small lateral white spot just about the middle, and an elongate oblique white blotch on each side of 
the apex, nearly meeting above the spinners. Legs as in S. vittata, but darker. Ventral area pale and 
speckled. Vulva consisting of a broad transverse oval area, divided in the middle by a narrow longitudinal 
septum, forming on each side a large longitudinally situate oval disc, with circular convoluted ducts 
appearing within each area. Protarsus i. without lateral spines; tibia i. with a lateral spine on the 
inner side ; tibia iii, and iv. with a small dorsal basal spine. 
Hab. Mexico, Amula in Guerrero (H. H. Smith). 
15. Sidusa cristata, sp.n. (Tab. XVI. figg. 10, 10 a-c, 2.) 
Type, ¢, in coll. Godman & Salvin. Total length 5 millim, 
Hab. Mexico, Teapa (H. H. Smith). 
This beautiful species may be at once recognized by the crested fringes of long brown 
