Mr. J. Blackwall on new Species of Spiders. 451 
the same division of the body as those preceding it. It may 
even be taken as a rule that all the dower Crustaceans (Xiphura, 
Branchiopoda, Ostracoda, Copepoda, and Cirripedia) have typi- 
cally ¢wo pairs of foot-jaws, never more, while the Malacostraca 
have either three pairs or only one pair,—and, further, that the 
former have only one pair of maxille, while the Decapoda and 
other Malacostraca have generally ¢wo pairs. 
“Thus in order to obtain at the same time a uniform and prac- 
tically useful terminology for the class Crustacea, it seems to 
me advisable to abolish in that group the utterly meaningless 
divisions thorax and abdomen, and to adopt those which I have 
now put forward, viz. head, trunk, and tail.’’ | 
LVII.—A List of Spiders captured in the South-east Region of 
Equatorial Africa; with Descriptions of such Species as ap- 
pear to be new to Arachnologists. By Jonn Buackwatt, 
F.LS. 
My friend Mr. Meade having transmitted to me for examination 
a second collection of spiders, made in the south-east region of 
equatorial Africa by the late Mr. Richard Thornton and Mr. 
Horace Waller, the result of my investigation of the specimens 
contained in it is givén in the following list. 
Tribe Octonoculina. 
Family Lycosipz. 
Genus Crenus, Walck. 
Ctenus vagus, 0. sp. 
Length of the female 14 inch; length of the cephalothorax 4, 
breadth 4; breadth of the abdomen 2; length of an anterior 
lez 22; length of a leg of the third pair 14. 
The eyes are disposed on the anterior part of the cephalo- 
thorax in three transverse rows ; the two anterior ones, with the 
two intermediate ones of the four constituting the second row, 
describe a trapezoid whose shortest side is before; and each of 
the two eyes forming the posterior row, with a lateral one of 
the second row, is seated on a tubercle; the intermediate eyes 
of the second row are the largest, and the lateral ones, which 
are in a line with them, much the smallest of the eight. The 
eephalothorax is compressed before, truncated in front, rounded 
on the sides, which are depressed and marked with furrows 
converging towards a narrow indentation in the medial line of 
the posterior region; it is clothed with short brownish-yellow 
hairs, and is of a dark reddish-brown colour, with narrow, brown 
lateral margins. The falces are powerful, conical, vertical, and 
