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



Cottus, Art. 



Cottus hathijhius (PI. X. fig. C). 



D. 5 I 10. A. 7. P. 17. V. 3. 



The praeoperculum is very strongly armed ; there are two spines arising from the 

 same root at the angle, one in front of the other, the posterior being longer than the 

 eye ; three other shorter spines along the lower edge of the prgeoperculum ; operculum 

 with a small spine at its antero-inferior angle. A pair of spines on the occij)ut behind a 

 deep depression occupying nearly the whole of the vertex. Eyes longer than the snout, 

 close together. Minute teeth on the vomer, but none on the palatine bones. Tail much 

 attenuated. Pectoral fin extending beyond the origin of the anal ; ventrals not reaching 

 the vent. Second dorsal fin higher than first : length of the caudal two-fifths of that of 

 the body (without head). Muciferous system much developed, opening by wide pores 

 along the lower jaw, the praeoperculum, the infraorbital ring and the lateral line. 

 Greyish-brown ; throat and all the fins black. 



Habitat. — South of Yeddo, Japan, Station 235 ; depth, 5G5 fiithoms. One specimen, 

 2^ inches long. 



It may appear matter for surprise to find a species of Cottus at so great a depth as 

 560 fathoms, and at first it did not seem to me improbable that the specimen 

 accidentally entered the mouth of the di-edge whdst it was near the surface. However, 

 on further consideration these doubts disappeared, as it is not very likely that a fish 

 living habitually at the bottom, as a Cottus must do, should be found floating far 

 from land ; moreover, the muciferous system is developed to an extraordinary degree, 

 much more so than in the littoral species of the genus. 



Centndermichthys, Richards. 



Centridermichthys uncinatus. 



Coitus uminattis, Reinh., Vid. Selsk. Natur. och Math. Afhandl., 18.33, p. xliv. 



,, hicornis, Reinh., loc. ciL, viii. p. l.\xv. 

 CentridermiclUhys uncinatus (Giinth.), Collett, Norsk. Nordh. Exped., Fisk., p. 29, tah. i. fig. 7; 



Forh. Vid. Selsk. Christian., 1880, p. 14; Nyt Mag. f. Naturvid., 

 xviii., 1884, p. 54. 

 „ „ Liitkcn, Kara-Uavcts Fisk. in Dijmphna-Togtot., p. 124. 



„ „ Lilljeb., Sverig. och Norg. Fisk., p. 161. 



An Arctic littoral species, more or less common in the sea between Greenland, 

 Spitzbergen, Nova Zcmbla, and Norway, extending in the western part of its range 

 southwards to the coast of New England. The Norwegian North Atlantic expedition 



