Leptocotis spinifera. 113 



pair of legs similar to the first; the third and fourth pairs simple, slender, 

 shorter than the fifth; the fifth, sixth, and seventh with the first joint 

 dilated ; the basal joint of the sixth broader than the fifth, but with 

 the remaining joints shorter, and closely pectinated along their an- 

 terior margin; the pectinations on the third joint coarse, on the fourth 

 very fine, while those on the fifth joint are intermediate between the 

 two preceding; the last pair of legs diminutive, not half as long as the 

 basal joint of the preceding. The first three segments of the ab- 

 domen subequal, inferior margins finely serrated, the third segment with 

 the postero-inferior angle produced into a long, spinous process, the 

 angle of the first and second segments square behind, not produced; the 

 peduncles of swimming feet broadly oval. Sixth abdominal segment and 

 telson elongated». 



Colour. ? 



Length. 8 — 13 mm (Streets). 



Hab. The tropical region of the Pacific (Streets). 



2. Leptocotis tenuirostris, C. Glaus, 1871. 



PI. V, fig. 10-14. 



Diniin. The head, without the rostrum, is about as long as the first 

 four peraeonal segments together; the rostrum is only a little 

 shorter than the rest of the head. 



The middle segments of the perœon are the longest, the follow- 

 ing decrease in length. 



The dactylus of the first two pairs of perwopoda is more 

 than half as long as the metacarpus. The whole seventh 

 pair are more than half as long as the femur of the sixth. 



The lateral parts of the first two pleonal segments are some- 

 what produced and rounded behind, that of the third seg- 

 ment is produced behind and sharp-pointed (?). 



Syn. 1871, Oxycephalus tenuirostris, C. Claus. 23, p. 155- 



1. » 27, p. 194 (48). 



» » » 36, p. 71, pi. 24, fig. 2. 



The original diagnosis of Oxycephalus tenuirostris from the year 

 1871 runs: 



»Schnabel überaus dünn und gestreckt ungefähr so lang als der 

 Kopf. Nackengegend desselben verengert und tief eingebogen. Körper 



Nova Acta Reg. Soc. Sc. Ups. Ser. IIL IG 



