FEOM SINGAPOEB AJ^D NEW ZBALAM). 20T 



The right mandible with a foot-like cutting-edge, five or six of the teeth representing 

 the toes in gradation of size ; inner plate not well observed ; molar tubercle very pro- 

 minent; palp with first joint short, second longest and stoutest of the three, carrying 

 spines at intervals on the indented straight margin, and a linear group of six on the 

 convex margin near its distal end; the third joint much curved, narrowing rather 

 abruptly for the distal half, with three spines on the concave margin and three at the 

 extremity, besides the fine down so commonly found on this joint of the palp. 



The left mandible differs a little, the stem behind the molar tubercle being appa- 

 rently longer, and the cutting-edge having three of its teeth much more prominent 

 than the other four. The secondary plate is thin, 5-toothed ; the spine-row, besides a 

 group of hairs at the base of the secondary plate, contains some six ciliated slender 

 sprues curving towards the molar tubercle. The number of teeth in the secondary 

 plate was visible in the new growth within the old shell. 



Lower lip, with the main lobes narrowing distally ; inner lobes not observed ; man- 

 dibular springs rather long and thin. 



Fu'st maxillae : broad distal end of the second incurved joint of the palp carrying 

 eight little spines ; outer plate crowned with ten spines distally spinulose ; inner plate 

 on its oblique indented margin carrying a row of fifteen slightly plumose bristles. 



Second maxillae : outer plate projecting beyond the inner, about equal to it in 

 breadth ; spines of various lengths, slightly ciliated, on its distal end ; inner plate with 

 convex margins, a row of distal spines, and a long row on the surface within the inner 

 lateral margin. 



MaxilLipeds with long inner plates reaching as far as the distal end of the first joint 

 of the palp, three teeth and several finer ciliated spines on the distal margin, eight 

 bristles along the inner margin ; outer plates not reaching to the end of the second 

 joint of the palp, having spine-teeth along the inner margin, the series passing over on 

 the distal margin into ciliated spines ; second joint of the palp longest, fringed on the 

 inside with bristles, this and the first and third joints dilated distally ; finger fringed 

 with fine hairs, ending in a nail-like spine or a spine-like nail. 



First gnathopods : side-plates oblong, with some fine spines or spinules about them ; 

 first joint not so long as hand and wrist combined; second joint short; third short,, 

 rhomboidal, with a fascicle of spines on the distal margin ; fourth joint longer than 

 hand, dilated distally, spinous on both margins ; hand a little dilated distally, palm 

 oblique, with spines along it and two stouter ones at the end for the finger to impinge 

 against, a row of four bristles on the inner surface besides those on the front and hind 

 margins of the hand. 



Second gnathopods: side-plates similar to those of the first pair, but larger; first 

 joint shorter than hand and wrist combined, less spined than that of the first pair; 

 second joint longer than third ; third joint as in the first pair ; fourth joint longer than 

 hand, distally widened, set with various groups of spines ; hand iiTegularly ovoid, 



VOL. XII. — PAKT VI. No. 4. — A;pril, 1887. 2 h 



