748 REV. O. P. CAMBRIDGE ON [Julie 18, 



Corfu, one on the Styrian Alps, and the rest near Nuremberg in 

 Bavaria. 



It is almost impossible to give, within any reasonable limits, such 

 descriptions of these minute Spiders (many of which are exceedingly 

 nearly allied to others already described) as will make them easily 

 determinable from description alone ; magnified figures are therefore 

 given of those portions of their structure upon which, par excellence, 

 specific distinctions are based— that is, the form of the cephalothorax 

 and the form and structure of the palpi and palpal organs of the 

 adult males. Wherever possible, the form of the genital aperture in 

 the females is also figured. There are, apart from their minute size, pe- 

 culiar difficulties in the determination of Spiders of the genus Erigone 

 (taking that to include most of Neriene, Bl., and all of Walckenaera, 

 id.); but as I am engaged at the present time in collecting materials for 

 an attempt to recast the arrangement of the numerous species con- 

 tained in it, I do not propose here to enter upon those difficulties, 

 further than to remark that every fair description, and all good figures 

 of the above noted portions of structure of any species supposed to be 

 new to science, will most materially assist towards a complete and 

 satisfactory monograph upon the whole group, which now includes 

 several hundred species. 



Erigone (Neriene, Bl.) arietans, sp. n. (Plate LXV. fig. 1.) 



Male adult, length J-g- of an inch. 



The cephalothorax is glossy and of a deep blackish-brown 

 colour, margined with black, the normal grooves and indentations 

 being indicated by yellow-brown ; the legs are orange-yellow, and 

 the abdomen black ; the palpi are of a dull greenish-yellow colour, 

 the radial and digital joints strongly suffused with black. The fore 

 part of the caput, where the eyes are seated, is a little prominent ; 

 the clypeus is impressed in the middle, but prominent at the lower 

 margin, and its height equals two thirds of that of the facial space ; 

 the profile line of the cephalothorax is a little depressed near the 

 junction of the caput and thorax. 



This species is closely allied to Neriene subtilis (Cambr.), which 

 it resembles in the form of the digital joint of the palpus ; but the 

 form of the cubital joint is very peculiar, and at once distinguishes 

 it from all other species known to me. This joint is produced to 

 near double its length in front, in an obtusely pointed prominent 

 form ; the radial joint is also slightly produced at its extremity, 

 rather on the outer side ; the digital joiut is large, with a small 

 pointed prominence at its base on the inner side, and a large sub- 

 conical one near the middle on the outer side ; the palpal organs 

 are prominent and complex, with corneous spiny processes. 



A single example found by Dr. L. Koch at Nuremberg, and sent 

 to me for examination. 



Erigone (Neriene, Bl.) incomta, sp. n. (Plate LXV. fig. 2.) 



Male adult, length Jg of an inch. 



The cephalothorax is of a deep shining black-brown colour, and 



