CKUSTACEANS FKOM THE TEOPICAL ATLANTIC. 369 



The limbs differ very little from the third peraeopods, unless the second joint be a little 

 longer and the sixth a little shorter than in that pair. 



Fifth perceopods. These are minute, with a shortly pear-shaped dilated portion that 

 may be taken to represent the second joint, which is immediately followed by a much 

 shorter and very much narrower piece carrying at its truncate apex the tiny finger, 

 broad at the base, and slender at the strongly bent tip. 



The pleopods are not very robust, with very small coupling-spines. The outer 

 branch has four and the inner three or four joints. 



The first uropods have the peduncle about four times as long as the branches, with 

 sixty or more spinules along the inner margin and many along the outer one. The 

 branches do not reach quite to the extremity of the telson : the outer is bordered 

 with nine long spine-like teeth on each side ; the inner, which is slightly the shorter, 

 has eighteen teeth on the inner margin, small near the base and larger behind ; the 

 outer margin has eight teeth, and its upper part unarmed. The second pair have the 

 peduncle subequal in length to the two coalesced segments of the pleon, the outer 

 branch a little more than half as long as the inner, carrying about six teeth on each 

 margin : the inner branch has six long teeth and one or two very small ones on each 

 margin ; it is coalesced with the peduncle, which has about fifteen small teeth on the 

 inner margin, and apparently a smaller number on the outer. The third pair have the 

 peduncles intermediate in size between those of the first and second pairs, subequal in 

 length to the telson, not twice as long as the coalesced inner ramus, with many teeth 

 on two margins, the upper ones small and distant. The outer ramus is not half as 

 long as the inner ; it carries six long teeth on the inner margin, and two or more on 

 the outer. The coalesced inner ramus has about fourteen teeth on each margin. 



The specimen was a little less than half an inch long. 



HaMtat. Atlantic. Lat. 0^ 38' 6" N., long. 6° 25' 8" E., off St. Thomas's Island. 

 Taken with the tow-net at noon from a depth of 10 fathoms. 



The specific name is given in remembrance of the vessel by aid of which the present 

 collection of Amphipoda was made. 



Rhabdosoma brachyteles, n. sp. (Plate LV. B.) 



The head is considerably shorter than the pleon to the extremity of the uropods, and 

 has the rostral not greatly longer than the part behind the first antennae. Of the 

 perseon-segments the fourth, fifth, and sixth are the longest. The first three pleon- 

 segments have the postero-lateral angles blunt, not produced backwards: these 

 segments are subequal in length ; the fourth is slightly shorter ; the coalesced remainder 

 of the pleon scarcely longer. The telson is very bluntly pointed, not so long as the 

 combined fifth and sixth segments, with which it is itself coalesced. 



The eyes and antennae are as in the previous species, and the same may be said of 

 the minute gnathopods. 



