IS83.] REV. O. p. CAMBRIDGE ON NEW SPIDERS. 353 



Button ; and to Mr. J. J. Rivers of Berkeley, California, for the 

 exceedingly remarkable species (allied to the European ^#y;;M«) from 

 that region. Want of leisure alone has prevented my being able as 

 yet to work out more of the valuable collections received from all of 

 the above sources. 



T H E R A P H O S I D jE. 



Theraphosina, 

 Sarpedon, g. n. (nora. propr.). 



Cephalothorax as broad as long, tolerably convex above, rather 

 higlier a little in front of the thoracic indentation than at the eyes ; 

 no lateral marginal indentation at caput ; that at the thoracic junction 

 is long, deep, transverse, and very nearly straight, if any thing the 

 slightest possible curve has its convexity directed forwards. The 

 height of the clypeus is equal to about half that of the facial 

 space. 



The eyes are unequal in size and form a rather large transverse 

 rectangular space as nearly as possible double as long as it is broad ; 

 two of the largest form a transverse line in the middle of the space, 

 separated from each other by somewhat more than a diameter's 

 interval, and each with the other eyes on its side forms an equilateral 

 triangle ; contiguous to each of the hind-lateral eyes is that one 

 which corresponds to the hind-central in ordinary Spiders ; it is very 

 minute and of a pearly white colour. 



Legs short, strong ; not very unequal in length, 4, 1, 2, 3 ; they 

 are furnished with hairs (but not densely), and a few fine, bristle-like 

 spines beneath those of the first and second pairs ; a well-expanded 

 dense scopula occupies the underside of the tarsi and metatarsi of 

 the first and second pairs ; the tarsi end with two (apparently 

 untoothed) claws, and beneath them is a dense claw-tuft. 



Tlie palpi are clothed like the legs, with a scopula beneath the 

 digital joint, which ends with a single simple claw. 



Maxillce rather long, strong, cylindrical, with the slightest possible 

 prominence at their extremity ou the inner side ; towards their base 

 on the same side is a short straight transverse row of (2-4) small 

 black but distinct denticulations. 



Labium of fair size, and quadrate in form, a little longer than 

 broad ; the apical margin is straight and armed with a single row of 

 sharp black denticulations. 



Sternum longer than broad, and broader towards the hinder part 

 than in front. The hinder extremity is drawn out into a point be- 

 tween the insertion of the basal joints of the fourth pair of legs. 



Abdomen short, and projects well over the base of the cephalo- 

 thorax. 



Spinners 4, the superior pair short, 3-jointed, very strong, and 

 upturned as is usual in this family ; those of the inferior pair very 

 minute, cylindrical, and placed close beneath, in fact almost between, 

 the superior ones. 



