STEBBING— ISOPOD A 1 9 



It is not without anxiety that I distinguish this species from that which in Professor 

 Eerdman's Pearl Fishery Report I named Jauira ? nana, from the Gulf of Manaar. On 

 re-examining the details of that minute form I find some inaccuracies in my former account. 

 The light mandible has no accessory cutting plate, the bidentate appearance spoken of 

 being due to two closely approximate spines. The first pleopods of the male were said 

 to end in two pairs of overlapping shortly lanceolate lobes, and these are figured as of 

 equal length. The fact, however, is that the outer lobe is produced beyond the inner, 

 this inner one having on its sharp apex and outer margin several setae, some of which 

 gave the impression of a prolongation of the lobe itself. The first correction brings the 

 two species into harmony, the second is concerned with a feature by which the two forms 

 seem sharply distinguished. A third form, Janira minuta, H. Richardson, from Bermudas, 

 is evidently in close relationship to the other two. The new species has the following 

 characters. 



In the male the head is without conspicuous rostrum, the fourth and fifth segments 

 of the peraeon are the shortest and the sixth is the widest. The pleon is almost smooth- 

 rimmed. 



The eyes are prominent, lateral. The first antennae have the first joint stout, 

 followed by two successively much smaller, with a flagellum of nine joints, each of the 

 last five carrying a filament. The first four joints of the second antennae are short, the 

 third the longest, with a small cylindrical exopod. The two following joints of the 

 peduncle are missing from all the adult specimens, but that these are at least moderately 

 long and carry a many-jointed flagellum may be inferred from the condition of these 

 appendages in the marsupial young, where the flagellum is already eight-jointed. 



The upper lip is longer in proportion to its breadth than in J. nana. The cutting 

 plate of the mandibles is divided into five teeth on the left and seven on the right member, 

 the accessory plate on the left has seven teeth ; there are six spines in the spine-row. 

 The first maxillae have four fine setae on the inner plate. The second maxillae and 

 maxillipeds are in practical agreement with those of J. nana. 



The first gnathopods have the fifth joint in the male with its hind margin produced 

 into a strong tooth, the interval between this and the finger hinge being occupied by 

 a shorter tooth, which is however produced a little beyond the outer one. In ./. nana 

 the structure is nearly the same, but the two teeth are much less conspicuous. In J. 

 rturmta thei-e is a much longer outer tooth produced much beyond two shorter intermediate 

 teeth. In all the three species the narrow sixth joint is capable of folding down along 

 the whole length of the fifth, and ends in a minute finger or nail-tipped seventh joint. 

 The first gnathopod of the female is not known for J. nana, but, from the analogy of 

 J. minuta, it may be supposed that it has the fifth joint fusiform, not distally dentate, 

 and this is the case in the female of J. crosslandi. The other limbs of the peraeon follow 

 the custom of the genus. In the present species the fifth peraeopods appear to be decidedly 

 the longest. 



The first pleopods of the male show marks of separation so decided between the 

 upper part and the part below the constriction that I think this lower part should be 

 regarded as constituted by one or both of the rami ; its convex outer margins are produced 



