F, P. SMITH ON THE SPIDERS OF THE SUB-FAMILY ERIGONINAE. 19 



spiders, including the smallest known representatives of the 

 order. It seems to be an offshoot from some of the more 

 specialised forms of the Neriene group, and is characterised by 

 the sternum being at least as broad as long, and by the elevation 

 of the male caput, which is usually present, affecting to a greater 

 or less extent the position of the eyes. Many of the species 

 included in this group are of most grotesque form, and the 

 variations in structure of the male caput and palpi are of 

 great interest. The identification of the females, as in the 

 Neriene group, is often a matter of great difficulty, and the 

 surest and most reliable characteristic is, as a rule, the armature 

 of the genital aperture. In some species of this group the 

 abdominal integument becomes coriaceous, especially in the 

 genus Lophocarenum. 



The Walckenaera group contains a moderate number of spiders, 

 which are, as a rule, rather large compared with the average 

 size of the Erigoninae. The sternum is usually considerably 

 longer than broad, the cephalo-thorax somewhat elongate, and 

 the tibia of the male palpus furnished with prominent apophyses. 

 The palpal tibia of the female is longer than the patella, and 

 usually somewhat enlarged towards its extremity, and the tarsus 

 of the palpus is, in this sex, more acuminate than in the majority 

 of the Erigoninae. The form of the male caput varies to a 

 remarkable degree. In the genus Cornicularia there is simply a 

 small process, varying in form with the species, projecting from 

 the centre of the ocular area. In Walckenaera the caput may 

 be quite normal, or it may be remarkably modified. In W. 

 acuminata we have, perhaps, the acme of eccentricity. The 

 caput of the male is elevated in the form of a long slender 

 curved prominence, which carries the entire ocular group. Four 

 eyes are placed near the middle of this prominence, which is 

 there somewhat dilated to accommodate them, the remaining 

 four being at the apex, which is also somewhat expanded, and 

 is ornamented with a number of minute hairs. 



Detailed generic or specific descriptions of these minute 

 arachnids would be quite out of place in this purely intro- 

 ductory communication, but I append drawings of a few 



