COPEPODA. 25 



nearly of same length, masticatory plate with strong teeth. The posterior foot jaws 

 with first and second basal and Ri in proportion of 24 : 11 : 20 ; maxillge, B 2 with 5 ; 

 Re with 10 ; Ril with 4, Ri2 with 3, Ri 3 with six bristles, Li 2 and 3 present, and 

 Le 1 with eight bristles. 



The first feet have one jointed Ri and three jointed Re, without Se on i?e 1. 



The second feet have two jointed Ri and three jointed Re. 



The third and fourth feet have both rami three-jointed! 



Fifth feet comparatively large, that of the right side a little longer than the left. 

 Each of three segments, of which the two basals are equal in size, but the last segment 

 on the right foot is a little longer than in the opposite foot. Each has terminally 

 three spiny processes, the innermost comparatively thick, curved, and hook-like, and 

 with hairs only on the outer margin. The two outer spines are neither much more 

 than half the length of the inner one, and only half as thick. 



The ^ is a little smaller, 1 "75 mm., and of slenderer build ; the asymmetry of the 

 last thoracic segment is only slight, and on neither side is it so prolonged as in the 

 female. The abdomen consists of five segments, the first segment is more laterally 

 swollen than in the female, and is broader than long ; the second and third segments 

 about equal in length, and much longer than the anal, which is very short. The 

 antennse, oral organs and feet are the same as in the female, with the exception of the 

 fifth pair, which are converted into two extraordinary appendages. Arising from a 

 common basal, the right leg possesses four segments, the left five segments. In the 

 right leg the first joint is short and rather broad, the second elongated, rather longer 

 and thicker than the third, which is along thin joint with club-shaped distal extremity, 

 and having attached to the joint it makes with the last appendage a broad, rather 

 triangular plate covered with fine hairs and a few rather strong spines. The last joint 

 is represented by a comparatively strong and large curved appendage, armed along its 

 inner margin with short stiff" bristles, these two terminal appendages resembling an 

 awkward-looking pair of shears. 



The left foot, of five segments, has the first and second comparatively shorter but 

 broader than the third and fourth. The fifth segment short and broad at the distal 

 end, has externally a short curved tooth-like ending of the distal margin, and at the 

 inner end an upright knob-shaped appendage, strongly armed all over, and especially at 

 the base of the stalk, with short stiff' bristles. 



The fifth feet of the $ and ? possess no near resemblance to similar organs in any 

 other species of Stephus ; the size of the animal, moreover, is comparatively large for 

 any representative of this genus, and it must therefore be regarded as a new species. 

 Several examples occurred in two or three of the ' Discovery ' collections. 



