292 



SCANDINAVIAN FISHES. 



Reinii. (Ljparis), Overs. Dansk. Vid. Selsk. Forh. 1842, p. 



82; JoRD., Gii.B. (Careproclus), Bull. U. S. Nat. Mus., No. 



16, p. 740; Gthr (Liparis), Chall. Exp., Rep. Scient. Res., 



Zool, vol. XXII (Deep Sea Fish.), p. 67. 

 Liparis (Carepructus) Reivhavdi, Kr., Naturb. Tidskr. Klihvn, 



ser. Ill, vol. I, p. 252; Coll. {Careproctus), Vid. Selsk. 



Forh. Christ., 1880, No. 8, p. 1; Id., Norsk. Nordh. Exped.. 



1876—78. Zool, Fiske, p. .57, (ab. II. figg. 15 et 16; 



LiLLJ., <6V., Norg. Fisk., vol. I, p. 682; Ltkn {Liparis), 



Dijmphna-Togtets Zool. bot. Udb., p. 152. 

 ? Liparis micropas, Gthr, 1. c, p. 66, tab. XII, fisr. B. 



Obs. GuNTHEH. as well as Jordan and Gilbert, lias returned 

 to Reinhardt's opinion that this species, as it occurs in Greenland, 

 is the same as the Kamchatkan species described by Pallas, from 

 Steller's notes and specimens. This point cannot be elucidated nn- 

 til well-preserved specimens have been obtained from the north of 

 the Pacific, but if we keep in mind the variations to which the spe- 

 cies of this genus are subject, and the geographical extension of the 

 preceding species, every possible fact urges us to recognise this iden- 

 tity. Pallas also states, in his Zoograpliia (1. c), that he has heard 

 on trustworth}' autliority that the species also occurs in the White 

 Sea. Whether GOnthee's Liparis micropus is not identical with this 

 species, is a question that may well be asked ; so exactly do his figu- 

 res and description apply to the specimens we have examined. The 

 number of the fin-rays (Z). 35 — 37; A. 35 — 36) is the only cha- 

 racter which might constitute a specific difierence; but here a slip 

 of the pen or some abnormity involuntarily suggests itself to us, for 

 in no other Cychgaster is the number of rays in the dorsal fin so 

 like that in the anal; and even if the number of rays in the anal 

 fin is as low as stated by Gunther, still the other characters are 

 against the recognition of the specific difference. 



The Slimy Sea-Snail is distinctly a deep-sea fish. 

 All the fishes of this description that we have pre- 

 viously treated of, are al)le to sustain life in the higher 

 marine regions, or are not confined to so great a depth 

 that the sha])e and structure of the true deep-sea fishes 

 have been forced upon them. Among the peculiarities 

 of the latter forms" we find, in the first place, their 

 loose structure, which is not restricted to the skin, as 

 in the other species of Cijclogaster (though in Cyclo- 

 gaster gdafinosus it attains its highest development), 

 but also affects the texture of the muscles and the 

 bones. Steller and Pallas compare the organization 

 of Cychgaster gelatinosus in this respect to that of tlie 

 Mediisce. Though tlie smaller specimens tliat we have 

 examined, are of only slightly looser structure than 

 similar examples of the preceding species, still the diffe- 

 rence is pronounced enough to distinguish the species 

 to some extent. Kroyer too, describes the skeleton as 

 "remarkable for its loose, spongeous structure and con- 

 sequent softness." Another characteristic of the deep- 

 sea fishes — also a retention or even a higher deve- 

 lopment of a juvenile character — lies in the large 



« Cf. GCnther, LUrod. Study of Fish., pp. 209 etc. (Ilandb 

 pp. XXIV etc. 



muciferous pores and cavities in the head, belonging 

 to the system of the lateral line; Init even in this 

 respect the Slimy Sea-Snail is to be regarded onlv 

 as a more advanced form than the preceding species. 

 This gradual progression in the same series of develop- 

 ment, which further expresses itself most distinctly in 

 the coalescence of the vertical fins, the greater number 

 of rays in the dorsal and anal fins, and the decreasing 

 depth of the tail, is all the more interesting as it is 

 accompanied by the reduction of the apparatus of the 

 ventral fins, and the removal in a forAvard direction of 

 this apparatus and also of the vent, an alteration which 

 is of systematical importance as a partial explanation 

 of the relations between the jugular or the apodal forms 

 and other types. During youth the position of the 

 ventral disk in those specimens of Cijclogaster gelatinosus 

 which we have examined, is only slightly different 

 from that which it occupies in Cyclogaster Montagui 

 or Cijcl. Fahricii. In these cases the distance between 

 it and the tip of the snout is 11 or \i % of the length 

 of the body (about 1 % less than in similar specimens 

 of Cycl. Ilontagiii), and only part of it lies under the 

 posterior part of the eye. In older specimens, however, 

 it is apparently moved considerably further forward: 

 in Kroyeu's specimen 183 mm. long, he states that it 

 was only 4^/^ mm. distant from the ])oint of the lower 

 jaw. This seems also to apply to the position of the 

 vent. The distance between it and the tip of the snout 

 in our specimens measures 20 or 21 % of the length 

 of the body. According to Pallas, this proportion 

 may sink to 9 %. 



Assuming that the Kamchatkan species is identical 

 with the Atlantic, the Slimy Sea-Snail attains a con- 

 siderable size. The specimen described by Pallas in 

 his Spicilegia was 495 mm. long, and in his Zoograpliia 

 he says that the species often attains a length of 2 

 feet. In Scandinavia and the Atlantic Ocean it is ex- 

 tremely rare, and only small specimens are found. In 

 1879 the zoologists on board the gunboat Gunlnld, 

 Professor Theel and Doctor TrybOxM, took four .speci- 

 mens about 60 mm. long, in the month of July, about 

 half-way between Arendal and the Skaw, at a depth 

 of from 350 to 370 fathoms and on a bottom of fine, 

 bi'own clay. On the Norwegian Arctic Expedition of 

 187G — 78 three specimens between 56 and 79 nun. in 

 length, were taken at a depth of from 263 to 658 



. Icblli., pp. 199 etc.) and Voy. Cliallenger, Rep., Zool., vol. XXII, 



