322 REV. O. p. CAMBRIDGE ON SPIDERS [Apr. 20, 



two basal joints and the hinder extremity of the femora yellow, each 

 one of the femora having a single annulus of the same colour. The 

 tarsi are of a pale hue ; and all the legs are furnished with short fine 

 hairs. 



The jmlpi are moderately long; the cubital joint is strong, some- 

 what clavate, and double the length of the radial, which is of a blunt- 

 pointed form, and adheres closely to the base of the palpal organs ; 

 the digital joints are large, of an oval form, with their convex sides 

 directed towards each other ; the palpal organs are compact, and not 

 very complex. 



The falces are long, not very strong, but projecting forwards. 



The form of the maxilla, labium, and sternum is normal. 



The abdomen has its hinder extremity considerably produced into 

 a large somewhat cylindrical prominence, rounded at its extremity ; 

 it is of a dull clay-yellow hue, with a black spot at the end of the 

 prominent portion, and another stronger one just above the spinners, 

 which are placed about halfway between the fore and hinder extre- 

 mity of the abdomen. Near the middle of the upperside are two 

 silvery-white spots in a transverse line, and two otbers behind them, 

 wider apart, one on each side of the produced portion. 



The female resembles the male in general colours and markings ; 

 but the legs are shorter, the cephalothorax wants the elevated bi- 

 lobed anterior part of the caput, and the abdomen is of a different 

 shape, being gradually elevated to a great height, and forming, when 

 looked at in profile, a nearly isosceles triangle whose base is much 

 shorter than its sides. The silvery markings also on the abdomen 

 are larger and more numerous, varying, however, a little in tbeir size 

 and form, that represented in figure Ic showing their greatest extent. 



This pretty Spider is qnasiparasitic, living in the webs of some 

 Epeirid, though I do not know of what species. It appears to be 

 an abundant species, numerous examples of both sexes having been 

 sent to me at different times from Ceylon by Mr. G. H. K. Thwaites. 



Argyrodes concinna, sp. u. (Plate XXVIII. fig. 2.) 



Adult male, length to the spinners 1 4 line, and to the apex of the 

 abdomen 2 lines. 



This species is allied to Argyrodes epeirce, Sim., but easily dis- 

 tinguishable by the form of the caput, and also by the form and 

 pattern of the abdomen. 



The inferior lobe of the fore part of the caput is almost as strong 

 as the superior one ; its extremity is rather upturned ; and the cleft 

 between the two is nearly obsolete, as, excepting at the base of the 

 cleft, the two lobes are in contact with each other. 



The cephalothorax, legs, and pal[)i are yellow-brown. 



The leys are long and slender, 1,2, ^1, 3 ; those of the first pair 

 exceed three times the length of the Spider itself; and the anterior 

 part of tlie tibise and femora of this pair is strongly suffused with 

 dark reddish brown ; their armature consists of fine hairs only. 



The paljji are very similar to tliose of A. epeirce ; but the struc- 

 ture t-f the palpal organ differs a little. 



