NOKWAV HADDOCK. 



149 



iSyii. Perca tnarina, Lin., Sijsi. iiat.. ed. X, toui. I, |i. 200 (t-.\cl. syn. 

 Art.); Fn. Siiec. ed. II, p. 118; Ltkn (Sebastes), \\d. Mecldel. 

 Natiirh. For. Kblivn, 1876, p. 358; Mai.m, Gbijs, Boh. Fn., 

 p. .^585; WiiNTH., Zool. Dan. Fi.tk-e, p. 11, tab. II, fig. 7; 

 Id., Naturh. Tidskr. Kblivn, sor. Ill, v(d. XII, p. 9; Com,., 

 Vid. Selsk. Forh. Clirist., 1871), No. 1, p. 7; Id., Norsk. 

 Nordh. Exped., Zoologi, Fiske, p. l.'i, pi. I, fig. 3 et 4; 

 LiLLJ., Sv., iVory. Fisk., vol. 1, p. 02; Jokd., Gii.b., 6'yji. 

 Fish. A. Amei:, Bull. U. S. Nat. Miis., No. IG p. 651; 

 Coll., N. Mag. Naturv., Christiunia, Bd. 29 (1884), p. 52. 

 Perca norvegica, Ascan., Icon. rer. nat., c;di. II, p. 7, tab. 

 XVI; MCll., Prodr. Zool. Dan., p. 46; Fabr., Fn. GroeiiL, 

 p. 167; Uetz., Fn. Suec. Lin., p. 336; Hollukko {llolo- 

 eentrus), Beskr. Boh. Fisk., part. Ill, p. 49 cum fig.; Cuv., 

 Val. (Sebastes), Hist. Nat. Poiss., vol. IV, p. 327, lab. 87; 

 NiLSS., Prodr. Tchth. Scand., p. 79; Kroy., Danm. Fiske, 

 vol. I. pp. 159 et 584; I&.y Naturb. Tidskr. Kbbvn, sor. 2, 

 vol. I, p. 268; Ekstr., Vet., Vitt. Samh. Handl., Ny Tidsf., 

 I, p. 36; NiLSs., Skand. Fn., Fisk., p. 91; GrTun, Cat. Brit. 

 Mils., Fish., veil. II, p. 95; Morn, Ufvers. V.-t.-Akad. Forh. 

 1864, p. 508; Coll., Vid. Selsk. Forh. Christ. 1874, Til- 

 livgsli., p. 19; Day, Fish. G:t Brit., Irel, vol. I, p. 42, 

 tab. XVIII. 

 Sebastes viviparus, Kroy., Naturh. Tidskr. Kbbvn, ser. 2, vol. 

 I, pp. 275 et 281; Ekstr., .Skaitd. Fisk., ed. 1, p. 197, 

 tab. 49 (Hebastes regiilas in tab.); Id., Vet., Vitt. Samb. 

 Handl., 1. c; NiLss., iSkand. Fn., Fisk., p. 97; Kroy., 

 Danm. Fiske, vol. I (Till.-eg), p. 585; Id., Voy. Scand. 

 (Gaimard), tab. G; Gthr, Cat. Brit. Mus., Fish., vol. II, p. 

 96; Gill, Proc. Acad. Nat. Sc. Pbilad. 1863, p. 333; Ltkn, 

 1. c; Cederstr., Of vers. Vet.-Akad. Fiirb. 1876; N:r 1, p. 

 64; Malm. 1. c, p. 386; Coll., Vid. Selsk. Forh. 1879, p. 

 9; LiLLj., 1. c, p. 101; Johd., Gii.b. 1. c, p. 652; Coll., 

 N. Mag. Naturv., 1. c. 



Obs. Kroyer regarded the .smaller form of 6'ebastes mariniis 

 as a distinct species, S. vifiparns, founding his opinion chiefly on 

 the difference in the reproduction", the colouring, the breadth of the 

 interorbital space, the length of the pectoral and ventral fins, the 

 number of rays in the dorsal and anal fins, and tlie number of the 

 vertebrse. Hereto Lltken added the difference in the geographical 

 range of the two forms — the smaller form does not occur, so far 

 as is known, within the Arctic part of the Atlantic — ; and Collett 

 pointed out the difference in the direction of the anterior spines of 

 the preoperculum, a remark which Lilljeborg also applied to the 

 preorbital spines. Tliis specific difference is indeed marked and mani- 

 fold enough to be employed in most cases, but on closer examina- 

 tion, as NiLssON also found, it sinks into an expression of different 

 stages of development and individual peculiarities. This is true of 

 the direction of tlie first spine both ou the margin of the preoper- 

 culum and on the lower margin of the preorbital bone. The changes 

 of development in Seb. viviparus clearly tend to prove that the po- 

 sition and the direction of these spines approach more and more to 

 those they have in the larger form, the so-called Seb. norvegicus. 

 In the smallest specimens of Seb. viviparus in the Royal Museum, 

 two specimens from Norw.iy 180 mm. in length, these spines are all 

 directed backward, the five preopercular spines being situated at fairly 

 equal distauces from each other, only the upper (posterior) ones a 

 little closer together — almost as in our figure of Scorjxsna dac- 



ti/loptera, though the spines in the young specimens of Seb. vivi- 

 parus are longer and more pointed — the two preorbital spines being 

 of fairly equal size and as acutely pointed as the others. The lower 

 part of the preoperculum is now elongated, and this bone, which was 

 at first of a fairly regular, arcuate form, approaches more and more 

 the form of a rounded angle. That this is due to the elongation of 

 the lower (horizontal) part, and its growth in a forward direction, is 

 shown just by the fact tlj.it the two lower (anterior) spines grow 

 farther and farther distant from the three upper spines and farther 

 and farther apart from each other: the first spine moves nearer the 

 articulation of the lower jaw. At the same time the first spine gener- 

 ally grows more obtuse (assumes a broader, triangular form); and in 

 a specimen from Stromstad, a male 207 mm. in length, the first spine 

 of the right preoperculum is flat, triangular and directed almost straight 

 downward, while that of the left preoperculum has the same form, 

 but the tip of the spine points distinctly in a backward direction. 

 The transition to Seb. norvegicus in this respect is, therefore, quite 

 clear. The specimens of the Roj'al Museum also show similar altera- 

 tions in the preorbital spines, which on the left side of a male Seb. 

 norvegicus from Archangel, 228 mm. in length, are of exactly the 

 same form and direction as on the same side of a female Seb. vivi- 

 parus from Siicke Fjord (Stromstad), 251 mm. in length. In the 

 large specimens of Seb. norvegicus we find, however, a character which 

 we have never observed in Seb. viviparns, namely that the anterior 

 margin of tlie posterior preorbital spine is sometimes furnished with 

 2 or 3 serrate teeth pointing downward. The pointing of the lower 

 jaw in Seb. norvegicus by the development of a protuberance on the 

 chin is a change of growth which in small specimens of this form, 

 sometimes at least, is no more prominent than in large specimens of 

 Seb. viviparus. The interorbital breadth in proportion to the size of 

 the eyes is subject to far too great individual variations to be of 

 use as a specific character. In two female specimens of Seb. vivi- 

 parus from Bohuslan, the one 226 ram. in length, the other 251 

 mm., the least breadth of the interorbital space is respectively 68 % 

 and 77 °o of the longitudinal diameter of the orbit: in a male from 

 Bohuslan, 207 mm. in length, the corresponding ratio is 63'^ "i, 

 and in a male Seb. norvegicus from Archangel, 228 mm. in length, 

 72 %. The number of rays in the dorsal, anal, and pectoral fins is 

 generally leSg in Seb. viviparus; but a specimen of Seb. norvegicus 

 in the Royal Museum has only 13 soft rays in the dorsal fin (another 

 has 16), and 3 specimens have only 7 soft rays in the anal fin- 

 Most specimens of Seb. norvegicus have 19 rays in the pectoral fins, 

 the rest 18; while most specimens of Seb. viviparus have 18, the 

 rest 17. The black spots are indeed less distinct when they appear 

 in Seb. norvegicus, as is shown in our figure of this form; but a 

 greater or less degree of distinctness in markings which are in other 

 respects exactly similar, can scarcely constitute a specific difference. 

 Of the specific characters given only the number of the vertebrse 

 remains — according to both Kroyer and Malji the smaller form has 

 only 30 vertebra?, the larger 31. But the case is the same in other 

 fishes, e. g. in the common Herring (Clupea harengus), a species in 

 which the smaller forms generally have fewer vertebne, and in which, 

 according to Heixcke '', the number of vertebrfe varies between 51 

 and 58. It, therefore, seems to us most natural to regard the two 

 forms of Sebastes as belonging to the same species, the one form, 

 Seb. viviparus, which is less pelagic and more probably confined to 

 the deep water among the islands and in the fjords, more persistently 

 and more constantly retaining the traces of the early stages of the 

 development of the genus from the Scorpsenoid type. To the history 



" Koren, quoted by Malmgren (Of vers. Vet.-Akad. Forh. 1867, p. 260), Liluebobg (1. c.) and Collett (1. c.) have proved, however, 

 that the larger form is also viviparous. 



'' Die Varictaten des Herings, 2;te Theil, p. 55. 



