348 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loe 



outer plate armed with nine serrate spine-teeth ; palp not reaching end 

 of outer plate and bearing one apical plumose seta. Maxilla 2: Inner 

 plate shorter than the outer and both well armed distally with long 

 slender spines. Maxilliped: Inner plate rather long, reaching to the 

 middle of the outer plate, and armed distally with three teeth and the 

 usual plumose spines or setae; outer plate shorter than the inner, 

 reaching to the middle of the second joint of the palp and armed on 

 the inner margin and rounding extremity with submarginal spines; 

 palp short and stout, second and third joints widened distally by a lobe 

 on the upper inner margin; fourth joint stout, bearing a row of short 

 spinules on inner margin and a sharp apical nail. The thud joint of 

 palp bears distally a dense brush of setae which is characteristic of 

 the genus. 



Gnathopod 1: Rather stout and strong, second joint widening 

 gi-eatly toward the middle, without lower front lobe, and having 

 several downward-curving spmes on the hind margin; fourth joint 

 about three-fourths as long as the fifth, and with lower front corner 

 acute; fifth joint about as long and wide as the sixth, and with a 

 broad rounding lobe below bearing a row of stout spines; sixth joint 

 longer than wide, widest at the palmar angle, and bearing a row of 

 forward-pointing spines on tbe distal hind margin; palm oblique, 

 nearly straight, armed throughout with short spines, bearing a stout 

 spine on the outside near the middle and a smaller spine on the inside 

 below the defining angle ; on the rounding defining angle is a slightly 

 raised cui-ved area thickly studded with, fine rasphke teeth upon 

 which the end of the seventh joint rests (fig. 2,a) ; seventh joint stout, 

 aquiline, fitting palm, and bearing a row of spinules on iimer margin. 

 Gnathopod 2: Much larger and stronger than 1, second joint not 

 much expanded, lower front corner roundingly quadrate, but not 

 produced downward, and hind margin bearing a few short doTXTiward- 

 curvlig spines; third, fourth, fifth, and sixth joints as shown in fig. 

 2,6; fifth joint without lower lobe in fully mature males; sixth joint 

 broadly oval, hind margin about as long as palm and bearing one or 

 two groups of short spinules; palm vcr}^ oblique, shghtly convex, 

 anned throughout with short spines, and defined by a slight protuber- 

 ance on the inside of which is a shallow depression or pocket bearing 

 two or three short spines; seventh joint rather strong, fitting palm 

 ^\•ith the apex resting in the shallow pocket on the inside of the de- 

 fining angle (fig. 2,6). In the younger or not fully mature males the 

 fifth joint of gnathopod 2 is produced into a narrow curving lobe 

 between the fourth and sixth joints (fig. l.c). 



Peraeopods 1 and 2 are alike in structure, but 2 a little the shorter 

 (fig. 2,c). Peraeopod 3 about equal in length to peracopod 1. Peraeo- 

 pods 3 to 5 much alike in structure, but 4 may be a little longer than 



