BRITISH STALK-EYED CRUSTACEA. 175 
short. The larger hand, which is on the left side, is short, the 
sides nearly parallel, flattened, the upper margin with two carine ; 
the outer side also with two carine, the inner surface rounded. 
These being the chief specific characters as alluded to, I will 
compare them with those of my own specimens. In the two 
just received from the Channel Islands the spine on the arm, 
referred to above, is wanting ; but the angle of the arm nearest the 
wrist is in the form of a spine, and from it the margin of the arm 
slopes down to the point at which the wrist is articulated. 
The third and smaller specimen, which, I believe, came from the 
same locality, is unlike them in this feature, nor is it like the 
figure in Bell’s work. It has a spine-like process situated as 
in the figure referred to, but instead of the edge of the arm 
being continued on the same plane beyond it, it slopes down to 
the joint, as in the case of the other two specimens, but at a 
greater angle. Thus Bell’s figure, my small specimen, and my 
two large specimens, illustrate the development of a spine into a 
marginal tooth, the stages possibly indicating different ages. I 
do not say this is so, but it is reasonable to infer it. 
Again Bell says that the left hand is the larger, but in one of 
my two new specimens the right hand is the larger, and as the 
structure of the hands is so very different, this is an important 
feature, as it shows that it cannot be relied on to determine a 
species. 
The larger hand is very massive, rounded, and smooth, except 
towards the fingers, where it is armed with rather long, pale 
coloured hairs on the inner surface. On the outer edge of the 
large claw there is a rib-like projection terminating forward in a 
spine, just above the fixed finger. This is not the case with the 
small hand. The movable finger of the large hand is very much 
hooked, and shuts over the curious fixed finger like the beak of a 
Crossbill. ‘The fingers on the small hand are much straighter, 
larger in proportion to the size of the hand, though they too 
cross like those on the large hand, but to a less extent. In my 
specimens also the rostrum is very small and simple, the eyes 
protected by arched continuations of the carapace, which becomes 
transparent, as if to permit the animal to see through it, whilst it 
affords a screen to its organs of vision. The tail plates are large 
and beautifully fringed with sete, and the central plate is armed 
with four spines pointing downwards. 
