1158 
SCANDINAVIAN FISHES. 
dernized, most nearly resembling in external form the 
preceding Sharks. This is best shown by the character 
drawn from the shape of the pectoral tins, and might 
also be expressed by the relative dimensions of these 
fins, but for the fact that the alterations of growth 
within the genus approximate the fry, or at least the 
almost viable foetuses, too nearly to the following ge- 
nera. The same remark essentially applies to the form 
and dimensions of the two dorsal fins. How closely 
the genus Squalus is allied, however, to the remaining 
genera of the family, appears from the rank long as- 
signed to a Mediterranean form, the so-called Squalus 
uyato of Rafinesque (1. c.), as an independent species 
of this genus, until Bellotti and Doderlein" disco- 
vered it to be a young form of Centrophorus granu- 
losus , an inhabitant of the neighbouring parts of the 
Atlantic 6 . Even between the two species left within 
the genus Squalus after this elimination there would 
appear to obtain some developmental relation, one of 
them ( Squalus Blainvillei ) representing in its cha- 
racters the juvenile and male characters of the 
other. 
THE PICKED DOG-FISH (sw. pigghajen). 
SQUALUS ACANTHIAS. 
Plate LII, figs. 1 and 2. 
Distance between each pectoral fin and the tip of the snout at most about V 3 (67 — 58 %) of that between the 
first dorsal and the same point. The ventral fins begin half-way along the body or somewhat further back. 
Syn. 'M.VMvd'lag yaleog, Aristot., Zool., lib. VI, cap. X (= Mu- 
stellus spinax, Gaza). Galeus acanthias, Rondel., De Pise., 
p. 373. Cams Acanthias , Gaz® spinax, Schonev., Ichthyol. 
Slesv. Hols., p. 29. Squalus pinna Ani nulla, ambitu cor- 
poris subrotundo, Art., Ichthyol., Gen. Pise., p. 66; Syn. 
Pise., p. 94; Spec. Pise., p. 102; Lin., Fna Suec., ed. 
I, p. 100; It. Wgoth., p. 174; Mus. Adolph. Frid., part. 
I, p. 53 ( Hundfi.sk ). Haae, Str6m, Sondm. Beskr., part. I, 
p. 280. Haafur, Olafs., Reise Isl. , part. I, p. 359; part. 
II, p. 989. 
Squalus Acanthias, Lin., Syst. Nat., ed. X, tom. I, p. 233; 
Bl., Naturg. Fisch. Deutschl., part. Ill, p. 74, tabb. 75 
(fig. 1) et 85; Retz., Fna Suec. Lin., p. 305; Blnvlle 
( Acanthorhinus ), Bull. Sc. Soc. Philoin. 1816, p. 121; Cuv. 
( Spinax , subg.), Regn. Anim., ed. 1, tom. II, p. 130; 
Nilss. (Squalus), Prodr. Ichthyol. Scand., p. 117; Bonap. 
(Spinax), Iconogr. Fna Ital., tab. 139; Sundev., v. We. 
(Squalus), Skand. Fislc., ed 1, p. 187, tab. 46; Jord., 
Gilb., Bull. U. S. Nat Mus., No. 16, p. 16; Lillj., Sv., 
Norg. Fna, Fisk., vol. Ill, p. 665. 
Picked Dog Fish, Penn., Brit. Zool. (ed. 1776), vol. Ill, p. 
88; Yarr., Brit. Fish., ed. 1, vol. II, p. 400; Couch, Fish. 
Brit. Isl., vol. I, p. 49, tab. XI. 
Squalus fernandinus, Molina, Chili, p. 229; Guichen. (Spinax) 
in Gay, Chile , Zool., tom. II, p. 365. 
Acanthias vulgaris, Risso, Eur. Merid., tom. 3, p. 131; Mull., 
Hle, Plagiost., p. 83; Schleg. in Sieb., Fna Japon ., Poiss., 
p. 304, tab. CXXXV ; Kr., Damn. Fisk., vol. Ill, p. 868; 
Nilss., Skand. Fna, Fisk., p. 731; Dum., Hist. Nat. Poiss. 
(uouv. su. a Buff.), tom. I, p. 437 ; Barb. Boo., Cap., Peix. 
Plagiost. Port., p. 21; Gthr, Cat. Brit. Mus., Fish., vol. 
VIII, p. 418; Coll., Forh. Vid. Selsk. Chruia 1874, Tilliegsh., 
p. 211; 1879, No. 1, p. 104; Winth., Naturli. Tidskr. 
Kbhvn, ser. 3, vol. XII, p. 58; Mor., Hist. Nat. Poiss. 
Fr., tom. I, p. 342; Doderl., Man. Ittiol. Medit., fasc. II, 
p. 86; Mob., Hcke, Fisch. Osts., p. 152; Day, Fish. Gt. 
Brit., Irel., vol. II, p. 315, tab. CLX, fig. 2; Storm, N. 
Vid. Sels. Skr. Trondhj. 1884, p. 45; Car., Prodr. Fnce 
Medit., vol. II, p 503. 
Acanthias americanus, Stor., Mem. Amer. Acad. Arts, Sc., vol. 
II, p. 506; vol. IX, p. 2.32, tab. XXXVIII, fig. 1. 
Acanthias Linnei, Malm, Gbgs, Boh. Fna, p. 624. 
The Picked Dog-fish belongs to the smaller Sharks. 
According to Day it attains a length of 12 dm. on the 
English coast; but in Scandinavia it does not exceed, 
so far as we know, one of about 9 dm. c New-born 
fry with obliterated navel measure about 22 — 25 cm. 
In the external form of the body the Picked Dog-fish 
is not unlike the Tope, but it is usually rather more 
elongated. The greatest depth of the body, just in front 
of the first dorsal fin, varies irregularly between about 
9 and \\ % (according to Kroner sometimes 8 or 12 %) 
of its length, the least depth between 2 and 2 1 / 2 % 
(according to Kroyer sometimes nearly 3 %) of the 
same. The latter depth measures between about 13 % 
a Man. Ittiol. Medit., fasc. II, p. 118, Nota. 
6 This might besides be taken for granted partly from Rafinesque’s description of the teeth of the upper jaw (denti minuti ed acuti), 
partly from ESarboza de Bocage’s and Capello’s figures of old and young specimeus of Centrophorus granulosus. 
c The Vega Expedition brought home a male 9V2 dm. long from Behring Island. 
