296 REV. T. R. R. STEBBING ON STALK- BY ED CRUSTACEA MALACOSTRACA 



which Kroyer in 1845 described as Pasijihae tarda, redescribed and figured under 

 the same name by Mr Kemp in 1910. Here, however, instead of the first five pleon 

 segments and much of the sixth being sharply carinate dorsally, the earlier segments 

 show no carina at all and on none is the carina sharply developed. In the fourth 

 perseopods the sixth joint is three-quarters the length of the fourth, instead of less 

 than half, as in P. tardus, and in the fifth pair the sixth joint is decidedly shorter 

 than the fourth, not about equal to it. In some other respects there may be traced 

 divergence between the two species, but with only one specimen of the new form 

 available, it is inexpedient to lay too much stress on minutiae. The distribution of 

 Kroyer's species extends northwards to Davis Straits and the coasts of Greenland, 

 but according to Kemp lat. 51° 54' N. is the most southern locality from which the 

 species has been recorded in East Atlantic waters, a very different part of the globe 

 from that in which the Scotia specimen was obtained. 



Locality— -Lat. 48° 00' S., long. 9° 50' W. ; depth 1332 fathoms; Station 450. 



The specific name is given out of respect to Miss M. J. Rathbtjn, the distinguished 

 American carcinologist. 



A species possibly belonging to this family was taken in lat. 39° 48' S., long. 

 2° 33' E. ; depth 2645 fathoms ; Station 468. Unluckily it is represented only by 

 the pleon, and that wanting the first pleopods. It is worth mentioning, as the 

 remaining pleopods by their great length and slenderness make some approach to 

 those in the genus Psathyrocaris, although here the exopod is scarcely more than 

 twice the length of the endopod. The sixth segment of the pleon is long and clearly 

 carinate ; the telson has two dorsal carinse, which are rather wide apart at the base. 

 The exopod of the uropods is elongate. 



Family Nematocarcinidse. 



1884. Nematocarcininie, S. L Smith, U.S. Fish Comm. for 1882, p. 368. 

 1888. Nematocarcinidse, Bate, Rep. Voy. " Challenger," vol. xxiv. pp. xiii, 481, 927. 

 1893. „ Stebbing, Hist. Crust., Internat. Sci. Ser., vol. lxxiv. p. 249. 



1901. ,, Alcock, Catal. Indian Deep-Sea Macrura, pp 56, 85. 



1910. „ Kemp, Fisheries, Ireland, 1908, pp. 35, 75. 



Alcock remarks that " the Nematocarcinidse in a logical system should not be 

 separated as a distinct family, for they are merely Pandalidse in which the first four 

 pairs of thoracic legs have delicate exopodites, and they might be united with the 

 latter family." But as in the Pandalidse " the thoracic legs never have exopodites," 

 and the fifth joint of the second pair is subdivided, while the Nematocarcinidse have 

 that joint simple, and in the three following pairs an interlocking arrangement 

 between the third and fourth joints described by Bate as of " peculiar and unique 

 character," the separation of the two families may very well be upheld, 



