318 ASELLIDA. 
Tue accompanying figure of this species has been made 
from Colonel Montagu’s typical specimens, described by 
Dr. Leach, in the British Museum. Not only do they 
differ from the J. Kréyerii of Milne Edwards, from the 
shores of La Vendée, in their much broader form, but 
they agree in this respect with Kréyer’s figure of J. nivalis, 
from Greenland, whilst the description of the tail given by 
Otho Fabricius of his Oniscus marinus (‘‘ cauda subciliata 
et extremitate incisuram vix notabilem habens, de qua 
styli duo brevissimi, acuti, distantes’’) seems also to 
accord with other British species. Dr. Leach, indeed, 
describes the eyes in his species as being ‘‘ placed close 
together,” but this character neither agrees with the type 
nor with the descriptions and figures of Kroyer and 
M. Edwards. The upper surface of the body is flattened 
and marked with irregularly impressed lines. The lower 
or outer pair of antenne are considerably more than half 
the length of the animal. The tail is much wider than 
long, being nearly semicircular in form, having two 
small impressed dots a little apart towards its basal por- 
tion ; the centre of the caudal margin has a nearly semi- 
circular notch, with the centre of the incision slightly 
produced into an obtuse point, on each side of which are 
implanted the minute uropoda. 
The general colour is ashy, but very much varied in its 
shades in dried specimens, with the front of the head 
whitish. 
Jera Hopeana of Costa (Faun. d. Regn. di Napoli fase. 
83, tav. iil.) appears to us identical with the present 
species, agreeing with it (contrary to Signor Costa’s 
statement) in the position of the eyes; the only apparent 
difference consisting in the equal size and apparently 
three-articulated structure of the two appendages of the 
minute terminal uropode. 
i 
