SOME ARCTIC SPIDEES. 615 



There are also some minute tubercles in a longitudinal row in 

 front of the femora of the first pair of legs, and each tubercle 

 bears a fine hair. 



Erigone Fisheri, sp. n. (PL 45. fig. 8.) 



Adult female, length 1| line. 



This species is nearly allied to E. psychropliila, Thor., but the 

 cephalothorax is distinctly longer in proportion to its width and 

 the lateral marginal impression at the caput is stronger. The 

 margins are very finely denticulate, the denticulations bearing 

 short hairs ; and the whole spider is of a duller and browner 

 hue. There ia also an angular prominence towards the 

 extremity of the maxillso on the outer side, and a longitudinal 

 row of minute hair-bearing tubercles on the anterior side of 

 the femora of the first pair of legs towards the outer margin. 

 The genital aperture is characteristic and different in form from 

 that of E. psychrophila, though bearing much resemblance to it. 



Several immature males accompanied the adult females, and 

 I believe them to be of the same species, but, apart from their 

 being adult, it is needless to give any description of them. 



EXPLANATION OF PLATE 45. 



Fig. 1. Erigone psychrophila, Thor., S > magnified. 



2. „ „ Cephalothorax and falces in profile. 



3. ,, „ Cephalothorax and falces from front. 



4. „ „ Portion of palpus, showing radial and digital 



joints and palpal organs. 



5. „ „ Palpus, excepting digital joint, in profile. 



6. „ ,, Femur of first pair of legs in profile. 



7. „ „ 5 . Genital aperture. 



8. Erigone Fisheri, Camb., 2 . Genital aperture. 



44* 



