Species of Sunamphithoe. 115 



of A. gammaroides. In one specimen out of five the flagella 

 agree with those described by Mr. S. Bate, tlie lower reaching 

 beyond the extremity of the superior. In the other four 

 examples the upper flagellum extends beyond the extremity 

 of the lower. 



The first gnathopods are similar in the two sexes. The 

 hand with its closed finger may be described as narrowly 

 ovate. The palm is oblique, but slightly defined, with a few 

 hairs rising from near the edge ; the finger a little overlaps 

 it. The second gnathopods differ in the two sexes, being more 

 quadrate in the male, more ovate in the female ; in both the 

 wrist is continuous with the hand, being slightly more dilated 

 in the female than in the other sex. The palm of the male is 

 remarkable, differing in shape on the inner and outer sides of 

 the hand ; it is bounded anteriorly by the bulging outwards 

 to a very moderate extent of the anterior edge of the hand, 

 whence it runs obliquely in two concave curves on the outer, 

 side to the base of the finger. The finger is large and power- 

 ful, serrated on the inner edge, and curving over to the extre- 

 mity of the palm, which, on the inner side, makes three curves, 

 the central and best-displayed one being not concave like the 

 others, but convex. The palm on this side has a small trian- 

 gular spine and several hairs springing from near its margin. 

 Between the two sides of the palm the hand appears to be 

 grooved or partially hollowed out. 



In the female the palm, though oblique as in the male, is 

 straight, with no tooth or special prominence to define it, 

 while the inner edge of the finger seems to be less concave 

 than in the male. 



The fourth, fifth, and sixth pairs of pereiopoda, which gra- 

 dually increase in length in the order named, agree rather 

 closely with those of Sunamphithoe hamulus, Spence Bate. 

 They have the distal extremity of the hand dilated, with a 

 large arcuate finger ; and near to where the inner margin of 

 this meets the palm, springs a long, blunt, curved spine, while 

 three or four other spines, also blunt, but short and straight, 

 are set on the rounded anterior portion of the palm. 



The telson, which moves up and down between the last pair 

 of pleopoda, and is thus sometimes completely hidden from 

 view in profile, has this peculiarity, that instead of a single 

 hook at its extremity it has a couple, with apparently a small 

 intervening level space. 



The last pair of pleopoda have two rami each — the inner 

 foliaceous, the outer (as in the allied species) armed with a 

 pair of spines so set as in conjunction with the ramus to form 

 hooks. The two preceding pairs of pleopoda are set with 



8* 



