- 3i — 



concave and the terminal portion very slender. In adult or 

 immature female spécimens the antennular peduncles are di- 

 stinctly longer and more slender than in N. microps. In adult 

 females the distance from the tip of meros of the elongate legs 

 to the end of the antennular peduncle is very conspicuously 

 longer than the sum of the two distal peduncular joints and 

 nearly as long as the whole peduncle. — In adult maies the 

 rostrum is shaped nearly as in the females. The antennular 

 peduncles are considerably thicker and somewhat or a good deal 

 shorter than in the other sex; especially the two distal joints 

 are thickened but show conspicuous différence as to length; 

 being either a little longer, or sometimes almost shorter, than 

 in the adult maies of N. microps. The distance from the tip of 

 meros of the elongate legs to the end of the antennular peduncle 

 is about as long as, or a little shorter than, the whole peduncle. 

 — Very young spécimens measuring 7-8. 5 mm differ in several 

 particulars from larger or adult spécimens. The cornea is very 

 oblong, its upper anterior half is light brownish, a little darker 

 above than below, and only a little broader than the lower po- 

 sterior half, which is very dark brown. Rostrum is long, seen 

 from above very oblong-triangular ; seen from the side the 

 upper outline behind the rostrum is somewhat elevated at the 

 dorsal organ, but less than in similar spécimens of N. microps. 

 My Atlantic spécimens have the elongate legs broken off. 



On the material secured by the Siboga a few remarks may 

 be set forth. Adult females have frequently the antennular 

 slightly shorter and the meros of the elongate legs proceeding 

 a little less beyond the tip of the antennular peduncles than in 

 Atlantic spécimens. An immature spécimen measuring io.5 mm 

 in length agrées with the description and figure of Sars in 

 possessing only 4 spines on the terminal joint of the elongate 

 legs, but their meros overreaches the antennular peduncle as 

 much as the length of the third peduncular joint; its eyes are 

 moderately oblong ovate, their upper anterior section being a 

 little broader and besides especially below conspicuously lighter 

 than their lower posterior section ; the rostrum is slightly longer 

 and at the base a little broader than that shown in fig. 6 of 



(42) 



