380 
SCYTODIDiE. 
SCYTODES THORACICA. PI. XXIX, fig. 272. 
Scytodes thoracica, Walck., Hist. Nat. des Insect. Apt., t. i, p. 270. 
— — Latr., Gen. Crust, et Insect., tom. i, p. 99. 
— — Blackw., Annals and Mag. of Nat. Hist., second series, vol. x, 
p. 353. 
— tigrina, Koch, Die Arachn., Band v, p. 87, tab. 167, fig. 398. 
Length of the female, ith of an inch; length of the cephalo-thorax, ith, breadth, Ath ; 
breadth of the abdomen, |th; length of an anterior leg, # 0 ths; length of a leg of the third 
pair, ^ths. 
The legs are of a brownish-yellow colour, with black annuli ; the first pair is the longest, 
then the fourth, and the third pair is the shortest; each tarsus is terminated by a short sup¬ 
plementary joint, into which two curved, pectinated claws are inserted. The short palpi 
resemble the legs in colour, and their digital joint in slender and pointed. The cephalo-thorax 
is large, oval, and remarkably convex, particularly in the posterior region, which is without an 
indentation in the medial line ; it is of a brownish-yellow colour, having a very irregular black 
line, extending from a prominence on each side of the frontal margin to the posterior gibbosity, 
irregular black marks on the sides and lateral margins, and a small black spot on which the 
anterior pair of eyes is seated. The falces are feeble, conical, prominent, armed with a very 
minute fang at the extremity, and of a brownish-yellow hue, with a black spot in front. The 
lip is short and rounded at the extremity; and the sternum is oval, with small prominences on 
the sides, opposite to the legs. These parts, with the maxillm, have a yellowish tint; several 
small black spots occur on the lateral margins and one in the middle of the sternum, and 
there is a spot of the same hue on the outside of the enlarged base of the maxillae, 
where the palpi are inserted. The abdomen is subglobose, slightly hairy, and of a pale, 
dull, yellow hue spotted with black ; on the upper part the larger spots are arranged in 
a longitudinal row on each side of the medial line, and those near the anterior extremity are 
confluent, forming one or more transverse lines; the spots on the under part are small and 
few in number ; the colour of the branchial opercula is yellow, and that of the very minute 
sexual organs red-brown. 
The male of Scytodes thoracica has not yet been discovered. The female inhabits the 
interior of houses, is slow in its movements, and carries its cocoon under the sternum, in which 
situation it is retained by the instrumentality of the falces and palpi. 
Dr. Leach lias stated in the supplement to the 4th, 5th, and 6th editions of the ‘Encyclo¬ 
paedia Britannica, article “ Annulosa, that two females of this species have been taken near 
Dover. 
