116 Rey. O. P. Cambridge on British Spiders. 
of the great development of the falces so conspicuously cha- 
racteristic of that sex. I have lately received an adult male 
of this spider from Mr. T. Workman, by whom it was found 
and kindly sent to me from the neighbourhood of Belfast. 
Erigone (Walckenaéra, Bl.) erythropus. 
Watckenaéra borealis, Cambr. Zoologist for 1862, p. 7967. 
W. erythropus, Menge, Cambr. Linn. Trans. xxviil. p. 453. , 
An adult male of this rare species was found among star- 
grass on the Studland sand-hills in June 1877. 
Erigone (Walckenaéra, Bl.) affinitata. 
Walckenaéra affinitata, Cambr. Zoologist, 1863, p. 8591; éd. Linn. 
Trans. xxvill. p. 454. 
In company with the last spider I also found a single 
example of the adult male of this very rare and distinct 
species. 
Erigone (Walckenaéra) atro-tibialis, sp. n. (Pl. XI. fig. 3.) 
Adult female, length 1 line. 
The cephalothorax is oval; the lateral constrictions on the 
margins of the caput are not very strong; but when looked at 
in profile there is a deep curved notch or indentation, caused 
by the slight elevation of the upper part of the caput and the 
rather unusual elevation of the thoracic junction. The colour 
of the cephalothorax is yellow; the caput and normal 
indentations strongly suffused with black. 
The eyes are on black spots and in two transverse and 
almost equally curved rows, forming an oval figure; the fore- 
most row is the shortest. The interval between those of the 
hind central pair is slightly less than that between each and 
the hind lateral eye next to it. The eyes of the fore central 
pair are nearly but not quite contiguous to each other, and 
appear to be rather the largest of the eight, the rest being 
very nearly of equal size. ‘The fore laterals are very near to 
(though distinctly separated from) the fore centrals; those of 
each lateral pair are contiguous to each other and are placed 
obliquely on a slight tubercle. The height of the clypeus is 
equal to half that of the facial space. 
The legs are moderately long, slender, not greatly differ- 
ing in length; their relative length appears to be 4, 1, 2, 3; 
they are furnished with coarse hairs and a few erect slender 
bristles, and are of a yellow colour, the tibiz of all four pairs 
‘being black. 
The palpi are moderate in length and strength ; the radial 
