and little-known Arctic SjJiders. 275 



tou-ards tlie labium, over wliich their extremities almost meet ; 

 thcj are also slightly curved, enlarged, and rounded on their 

 outer sides towards their extremity. 



The labium is of a subtriangular form, truncated at the 

 apex, the width at the middle being, however, rather greater 

 than at the base. 



The sternum is oval, pointed behind, of a yellow-brown 

 colour, margined with black, and with an indistinct blackish 

 central longitudinal marking. 



The abdomen is oval, very convex above, and projects 

 moderately over the base of the cephalothorax ; its ground- 

 colour is dull yellowish, clothed rather thickly with short 

 greyish hairs ,* the central longitudinal line of the upperside 

 is occupied by a long dark band, broadest in the middle, with 

 angular points on its sides, and pointed both at the fore margin 

 of the abdomen and just above the spinners, where it ends. 

 The fore part of the band is black, the rest dark yellow-brown 

 margined with black (the margins differing in breadth and 

 intensity) and comprising indistinctly the ordinary transverse 

 angular lines or chevrons in its area. The rest of the upper 

 surface is thinly speckled with black ; and the sides are marked 

 Avith blackish and somewhat oblique lines and markings ; the 

 underside is similar in colour to the upper, and has a central 

 longitudinal blackish line, with another, broken and less con- 

 spicuous, on each side. The spinners are short and strong ; 

 and at the base, immediately in front of the two inferior ones, 

 is the transverse inframamillary organ always found corre- 

 lated (at least in the female sex) with the calamistra of the 

 metatarsi of the fourth pair of legs. 



A single example taken in July 18G7 near the Illartlek 

 glacier. North Greenland, was received from Mr. E. Whymper 

 in 1870. It is closely allied to, but, I think, distinct from, 

 Dictyna hamifera^ anotlier Arctic spider, described by Dr. T. 

 Thorell in 1872. 



Fam. Agelenides. 



Gen. Tegenaria, Latr. 

 Tegenaria detestabilis, sp. n. 



Adult female, length 3:f lines. 



This spider is very closely allied to 2\ Derliamii, Scop., 

 resembling it in general form and structure ; it is, however, 

 smaller, paler in colour, and the fakes are not prominent at 

 their base in front as in that species. 



The Avhole spider is of a pale dull brownish yellow colour, 



