264 " THETIS " SCIENTIFIC RESULTS. 



margin subtruncate, with three small denticles ; the median is 

 rounded, and as long as the lateral ones. 



Eyes longer than broad ; the pigmented area is cuneate in out- 

 line, with the narrow end directed backwards. Basal joint of 

 first antennae stout, twice as long as broad ; second joint short — 

 its length is about equal to two-thirds the width of the first ; 

 third joint slender, half the length of the first. Flagellum con- 

 sisting of twenty-three articulations ; the first joint is equal in 

 length to the three following, the rest are subequal ; each has a 

 few setae on the inferior distal margin. First joint of the second 

 antennae a little longer than broad, not wider than those succeed- 

 ing ; second joint one-third longer than the first, and about the 

 same shorter than the third ; fourth joint equal in length to the 

 two preceding combined. Flagellum with seventeen joints, the 

 first being equal to the two following, third, fourth, and fifth 

 equal, the rest gradually increase in length to near the apex. 



Mandibles stout, nearly straight, cutting edge entire, with an 

 accessory trilobate denticle and a series of spines, the larger of 

 which bear one or two spinules. Molar tubercle ill-defined, and 

 rather remote from the cutting edge. Palp one-third shorter 

 than the mandible, the first joint longer than the second or third, 

 which are equal. Inner lobe of first maxillae slender, tipped with 

 four pectinate spines ; outer lobe with twelve simple curved spines 

 on the distal extremity. The lobes of the second maxillae have 

 their apices armed with pectinate setae or spines ; those on the 

 outer lobes have the spinules forming the pectination very minute. 



Maxillipedes with distal and proximal portions of the second 

 joint equal in size ; the former bears on the distal margin, and 

 also on the external surface, a dense series of stout pectinated 

 setae, and a short curved filament on the inner border. Second 

 joint of palp very broad distally, equal in length to the two suc- 

 ceeding ; fifth joint short, about equal to the fourth, and also to 

 the superior lobes of third and fourth. The first pair of legs is 

 imperfect, the succeeding pairs have the fourth, fifth, and sixth 

 joints covered inferiorly with numerous short, closely-placed 

 yellow hairs. Peduncles of the first three pairs of pleopods with 

 three or four spines on the interno-distal angle ; the inner ramus 

 of the first is triangular, the outer is narrowly obovate. Inner 

 ramus of the fifth pair a little tumid at the apex, with an elongate 

 papilliform lobe on the middle of the inferior distal surface, and 

 a bead-like tubercle on the inner margin below the suture ; each 

 process and the inner aspect of the distal border are clothed with 

 rather large rasp like denticles. Uropods a little unequal, inner 

 branch ovate-oblong, widest at the distal third, the outer distal 

 angle pointed, the apical margin obliciuely truncated on its inner 



