164 Mr. A. Randell Jackson on Spiders 



1. Leptyphantes sobrius, Thor. (i). 



Both males and females in Mr. Elton's collection, as well 

 as numbcMS of immature examples. L. lafehricola, L. K. (3), 

 which was obtained in Nova Zembla and Sil>eria, is possibly 

 the same species. Konig (lo) gave additional descriptions 

 of the female, but the sexuiil organs were not figured, nor 

 does there seem to be anv figure or description of the palpus. 



The paracymbium is of a very distinct shape, showing two 

 very prominent upwardly projecting processes between the 

 apex and base. The lamella characteristica issues from 

 behind the paracymbium ; it divides into two limbs, one above 

 the other. The upper one consists of a slender, slightly 

 curved, pointed, chitinous rod, from the lower side of which 

 springs a glistening white feathery fringe, the termination of 

 which forms a plume. The lower part is a semitransparent 

 fragile membranous plate, ending in a dark, strongly chiti- 

 nized, spine-like point. The tibia bears above six or eight 

 bristles about as long as the diameter of the joint. There are 

 several long hairs on the patella, which also bears on a slight 

 eminence on the upper side near the distal end a long strong 

 seta several times as long as the joint. Tlie tarsus bears a 

 blunt lobe on the outer side near the base. It is drawn out 

 into a point behind at the inner side. 



Length of articles : — patella '15 mm., tibia '15 mm., tarsus 

 •57 mm. 



The femora of the legs are all unarmed, except the first 

 pair, each of which has a spine on its ujiper third on the inner 

 side. The first and second metatarsi each show a single 

 spine above in the upper third. The third and fourth meta- 

 tarsi, in addition to this, show one at the same level beneath 

 and one a little lower on the outer side, tiiree in all. 



Colour and markings as in the female (i) and (10). 



The epigyne is fairly characteristic, but has a strong 

 general resemblance to that of several other species of the 

 genus. 



Advent Bay, Klaas Billen, Prince Charles Foreland. 



2 . Tlilaira glaciaUs,lL\\ov. ( i ) . 



Four adult males and one adult female. 

 Sexual organs figured by Kulczynski (9). 

 Klaas Billen, Advent Bay. 

 This species occurs also in Siberia. 



