872 THE VOYAGE OF H.M.S. CHALLENGER. 



Pleustes panopla, Kr0yer (sp.). 



1883. Amphitho'e paiwpla, Kr0yer, Gronlands Amphipoder, p. 270, tab. ii. fig. 9. 

 1840. „ ,, Milne-Edwards, Hist, des Crust., vol. iii. p. 41. 

 1846. „ „ Kr0yer, Voy. en Scaod., pi. xi. fig. 2, a-x. 



1858. Pleustes tuberculatus, Sp. Bate, Ann. and Mag. Nat. Hist., ser. 3, vol. i. p. 36;?. 



1859. Amphitho'e panopla ? {panoploides), M. Sars, Oversigt norsk-arct. Krebsdyr. 

 1859. Parainphithoe j-ianojyla, Bruzelius, Skand. Amph. Gamin., p. 69. 



18G2. Pleustes tuhenulatits, Sp. Bate, Brit. Mus. Catal. Amph. Cnist., p. 62, pi. ix. fig. 8. 



1862. ,, panaplus, Sp. Bate, Brit. Mus. Catal. Amph. Crust., p. 63, pi. i.x. fig. 9. 



1865. Paraviphitho'e pan(ypla, Goes, Crust, amph. maris Spetsb., p. 7. 



1870. ,, ,, Boeck, Crust, amph. bor. et arct,, p. 96. 



1874. Pleustes panophis, Buchholz, Die zweite deutsche Nordpolarfahrt, Bd. ii. p. 334, Taf. vi. 



1876. „ „ Boeck, De Skand. og Arkt. Amph., p. 302, pi. xxi. fig. 2. 



1882. „ „ Hoek, Die Crust, der Fahrten des "Willem Barents," p. 52. 



1884. „ „ Schneider, Crust, og Pycn. Kvasnangsfjorden, p. 97. 



1885. Pleustes panopla, G. 0. Sars, Den norske Nordhavs-Exp., p. 168. 



1886. Pleustes panoplus, Koelbel, Crust. Pycn. und Aracbn. von Jan Mayan, p. 7. 



Locality. — Station 49, south of Halifax, Nova Scotia, May 20, 1873 ; lat. 43° 3' 

 N., long. 63° 39' W.; ciepth, 85 fathoms; bottom, gravel, stones; bottom tempera- 

 ture, 35°. One specimen. Dredged. 



Remark. — It may be noticed that in this specimen the rostrum is proportionally 

 longer than in the figures of the species given by Kroyer, Boeck, and Sp. Bate. 

 J. S. Schneider observes that Boeck in his figure of the maxillipeds makes the first 

 joint of the palp too long, and produces the outer plate to the middle of the palp's 

 second joint, whereas in reality it only reaches the base. The Challenger specimen 

 agrees very well with Kr0yer's figures, but it seems scarcely possible that the figure 

 of Pleustes tuberculatus in the British Museum Catalogue can represent the same species. 

 Boeck, in speaking of the tuberculated form for which Professor M. Sars suggested the 

 name panoploides, declares that the apparent difference between the Norwegian aud 

 Greenland specimens rests only on an oversight of Kr0yer's. The matter seems to need 

 some further investigation. 



Pleustes ahyssorum, n. sp. (PI. LXVIL). 



Rostrum long and narrow, carinate underneath, and channelled on either side of the 

 carina, projecting over the first joint of the upper antennse almost to its distal end, 

 lateral lobes of the head very small, acute ; all the segments of the perseon and pleon 

 carinate, except the fourth of the pleon ; the back has an imbricated appearance, the hind 

 margin of the second segment of the pleon in especial being dorsally raised above the next 

 segment; the third segment of the pleon has a dorsal dentiform process erect near the distal 

 end ; the fourth segment has a dorsal depression ; the postero-lateral angle of the third 

 is produced in a small point ; in the two preceding segments this angle is not produced. 



