CRUSTACEA. 
91 
On looking over the Crustacea at the British Museum, I found a specimen of this species, with 
the nomen triviale here adopted attached to it, in the handwriting of Dr. Leach, but without other 
history. The present specimen was taken by Mr. Lay, at Woahoo, Sandwich Isles. 
Plate XXVII. Fig. 5. Squilla ciliata. 
5 a. Antenna media. 
5 b. Antenna lateralis. 
5 c. Pedipa/pus primus. 
5 d. Pedipalpus secundus. 
Legion EDRIOPHTHALMA, Leach. 
Ordo AMPHIPODA, Latr. 
Genus GAMMARUS Latr. Leach. 
Cauda stylis geminatis, superioribus stylis subeequalibus. 
30. Gammarus Typiilops. n. s. 
G. Icevis, pedibus anticis articulo ultimo subtus serrato , processu inter antennas subacuminato, oculis vix apparentibus. 
Long. corp. lin. 15. 
The body of this species is smooth and shining. The head is large, and vertical in position; it is 
overlapped by the first segment of the body. The first seven segments have lateral plates attached to 
them, of which that of the fourth is the largest. The legs, fourteen in number, are subequal, and termi- 
nate in simple curved claws, the first pair having in addition serrations along the under part of the 
last joint. Behind these are four pairs of spurious or natatory feet. The tail consists of six elongated 
processes, to each of which is articulated a pair of acuminate styles. A small triangular plate, 
which is bifid at the apex, overlaps the origins of the caudal processes. 
Plate XXVIII. Fig. 4. Side view of Gammarus Typhlops. 
4 a. First claw. 
5 b. Caudal styles. 
5 c, d. Head and antennae, magnified, 
of a specimen in which the superior antenna have lost some of the terminal segments, and end in a 
black convex speck. 
From the simple character of the feet, this species would probably have constituted a new genus 
with Dr. Leach; but as the superior antenna manifest the peculiar character {viz. the styliform 
appendage at the fourth joint) of the group to which he has restricted the term Gammarus, it has not 
been thought advisable to separate it. 
It is a native of the Arctic Seas. 
Ordo ISOPODA, Latr. 
Genus IDOTEA. Fabr. 
31. Idotea Entomon, Latr. 
Oniscus Entomon. Pallas, Spicil. Zool. fasc. 9. p. 64. tab. 5. fig. 1. 2. 6. 
This specimen, which measures four inches in length, was taken on the coast of Kamtschatka, 
N 2 
