REPORT ON THE AMPHIPODA. 1493 



of ocelli conterminous, of nearly equal extent, the upper groups triangular, the lower 

 almost circular. 



Upper Antennae. — Peduncle moderately stout ; first joint of flagellum longer than 

 the peduncle, set at right angles to it, carrying a large brush of filaments; second joint 

 attached at the apex of the first, a little longer than broad, having some long apical 

 filaments ; the third joint considerably longer and more slender, with filaments some 

 way from the apex ; the fourth joint much shorter and thinner than the third, with some 

 apical setules. 



• Lower Antennas. — Third (first free) joint of the peduncle rather more than a quarter 

 as long as the following joint, distally narrowed ; fourth joint long and slender, distally 

 widened ; fifth joint equal in length to the fourth ; first joint of flagellum slender, three- 

 quarters of the length of the preceding joint ; second joint rather more than half the 

 length of the first. 



First Gnathopods.- — Side-plates with convex front margin. The first joint a little 

 widened below ; the second longer than broad ; the third about three times as long as 

 wide, longer and broader than the fourth joint, with a hair-like setule at each apex and 

 one above the centre of the hind margin ; the fourth joint similar, but a little narrowed 

 distally, with a setule at each apex ; the fifth joint shorter and narrower than the fourth, 

 a little curved, distally narrowed ; the finger little curved, acute, less than half the 

 length of the fifth joint ; the whole limb perseopod-like. 



Second Gnathopods similar to the first, but scarcely so long, having the first and 

 second joints a little longer, but the third and fourth decidedly shorter, each of the 

 two latter joints having the apical setules and a setule near the middle of the hind 

 margin ; there is also a setule near the apex of the second joint. 



First Perieopods like the gnathopods, but rather longer, the difference in length 

 depending chiefly on the fourth and fifth joints which are about equal in length ; there 

 is a spinule near the hinder apex of the second joint and one high up on the hind margin 

 of each of the three following joints, besides subapical setules. 



Second Perieopods a little longer than the first. 



Third Perssopods. — The side-plates nearly as deep as the breadth, the margins 

 convex ; within the side-plates there is a long straight spine-like process pointing back- 

 wards. The first joint broadly oval, almost smooth-edged, a little shorter than the third, 

 fourth, and fifth joints together; the second joint scarcely longer than broad, with a 

 setule above the front apex ; the third joint very much shorter than the fourth, with 

 three setules on the front margin ; fourth joint longer than the fifth, with a setule at the 

 apex behind, and three setules on the front margin, which is sparsely and finely pectinate ; 

 the fifth joint slender, tapering, longer than the third, having three setules on the hind 

 margin and one on the front, which has a little scarcely perceptible pectination ; the 

 finger not a quarter the length of the preceding joint. 



