212 Amphipoda and Isopoda 



Third segment of the metasome (Plate IV., Fig. 1), with the 

 posterior lateral angle obtusely rounded. 



Eyes apparently quite absent. 



Superior antenna (Plate VI., Fig. 3) about equal in length to the 

 head and the first two segments of the mesosome combined ; peduncle 

 rather stout, equal in length to the head, first joint longer than the 

 remaining two taken together ; flagellum nearly three times as long as 

 the peduncle, composed of thirteen joints — the first joint equal in 

 length to two -sevenths of the whole flagellum, and bearing two rows 

 of sensory seta? ; accessory flagellum about half the length of the 

 main flagellum, composed of six joints, the first of which is slightly 

 longer than one-third of the whole accessory flagellum. There is a 

 single rather prominent and strong seta at the lower distal corner of 

 the first joint of the main flagellum. 



Inferior antenna (Plate IV., Fig. 4) extending to about the level 

 of the tip of the superior, and, therefore, as a whole, somewhat longer 

 than the latter ; rather slender ; peduncle armed with a few scattered 

 seta?, and having the fifth joint longer than the fourth ; flagellum 

 equal in length to the peduncle, composed of seventeen joints. 



Epistome (Plate IV., Fig. 2) remarkably prominent, projecting 

 almost entirely in front of the head (Plate IV., Fig. 2), as a large 

 compressed, linguiform, rounded lobe, overhanging the anterior lip in 

 front. 



Mandibles (Plate IV., Figs. 5 and 6) robust ; cutting edge with a 

 single small spine at the internal extremity, and a small tooth at the 

 other end, otherwise smooth ; molar process well developed ; between 

 the latter and the cutting edge there is a row of sette, among which are 

 to be found three or four strong simple spines ; palp elongate and 

 slender, arising at about the same level as the molar tubercle ; third 

 joint only half the length of the second, and bearing about fourteen 

 long simple seta?, while the second joint has about eleven seta? on the 

 distal part of its inner margin ; the left mandible bears, in addition, 

 near to the cutting edge, a short, stout, blunt, and slightly recurved 

 cylindrical spine. 



