ALLORCHESTES NILSSON11. 
41 
The eyes are not large, but round and black. The 
superior antennae reach to the extremity of the peduncle 
of the inferior. The inferior antennae are about one- 
fourth the length of the whole animal, with the peduncle 
about half the length of the antennae. The two basal 
joints are closely incorporated, but not fused, with the 
head. The mandibles are short, denticulated at the 
margin, furnished with a secondary plate, but destitute 
of any palpiform appendage. The foot-jaws are fur- 
nished at the apex with a sharp nail. The squamiform 
plates are three, two important, the third less so, fringed 
with short hairs. The first pair of legs have the hand 
oval, or nearly so, when the finger is shut : the palm is 
convex, and an obtuse tooth is placed just beyond the 
apex of the shut finger : the wrist is moderately pro- 
duced inferiorly. The second pair of legs have the hand 
much more developed, but formed upon the same type 
as the first. All the other pairs of legs terminate in 
curved pointed fingers. 
The squamiform basal joint of the four anterior pairs 
of limbs is as broad as deep, and nearly as deep as 
the respective segment of the body to which it is at- 
tached. Those belonging to the three posterior pairs 
are much shorter. The caudal appendages are short, 
stiff, and furnished with short, spine-like hairs. The 
middle tail-piece is single and small. 
This animal has, no doubt, been mistaken for the 
young of Orchestia littorea , to which it bears a general 
resemblance ; but it can readily be distinguished by the 
length of the superior antennae, which are rather stiff in 
their general appearance. 
The microscopic structure of the skin shows a distinc- 
tion (although not a very great one) from that of Talitrus 
and Orchestia. The t- markings are somewhat more nu- 
