1158 



SCANDINAVIAN FISHKS. 



dernized, most nearly resembling in external form the 

 preceding Sharks. This is best shown by the character 

 drawn from the shape of the pectoral fins, 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 fojtuses, 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 Squaluf> is allied, howe^■er, to tlie remaining 

 genera of the family, appeal's from the rank long as- 



signed to a Mediterranean form, the so-called SqiiaJus 

 uyato of Rafinesque (1. c). as an independent species 

 of this genus, until Bellotti and Dodehleix" disco- 

 vered it to be a young form of Centroplwrufi f/ianii- 

 losii.s, an inhabitant of the neighbouring parts of the 

 Atlantic \ Even between the two species left within 

 the genus S<pialus after this elimination there would 

 appear to obtain some developmental relation, one of 

 them (Sqiialiis BJoinviUei) representing in its cha- 

 racters the juvenile and male characters of the 

 other. 



THE PICKED DOG-FISH (sw. pioghajen). 

 SQUALUS ACANTHIAS. 



Plate LII, figs. 1 and 2. 



Distance hehveen each pectoral fin and the tip of the snout at most about *,3 {67 — 56^ %) of that between the 

 first dorsal and the same point. The ventral fins begin half-waij along the bodi/ or somewhat further bach: 



iSi/n. ^yi/.av^iag yaXeog, Aristot., ZooL, lib. VI. cap. X {= Mii- 

 stelbts spinax, Gaza). Gateus acanMas, Rondel., De Pise, 

 p. 373. Cams Acantliias, Gazm spinax, Schonev., Ichthyol. 

 Slesv. Hols., p. 29. Sgtiahis pinna Ani nulla, ambitii cor- 

 poris siibrotundo, Art., Ichthyol., Gen. Pise, p. G6; Srpi. 

 Pise, p. 94; Spec. Pise, p. 102; Lin., Fna Suec, ed. 

 I, p. 100; It. Wgotli., p. 174; Mus. Adolph. Frid., part. 



I, p. 53 {Hundfisk). Haae, StrSm, Sondm. Beskr., part. I, 

 p. 280. Ifaafvr, Oi.afs., Reise Isl., part. I, p. 359; part. 



II, p. 989. 



Squalus Acantliias, Lin., Syst. Nat., eii. X, turn. I, p. 233; 



Bl , Naturg. Fisch. Deutschl., part. Ill, ji. 74, tabb. 75 



(iig. 1) et 86; Eetz., Fna Suec. Lin., p. 305; Blnvllb 



(Acattthorhinus), Bull. Sc. Soc. Philoin. 1816, p. 121; Cuv. 



(Spinax, aubg.), Regn. Anim., ed. 1, tcmi. II, p. 130; 



NiLss. {Squalus), Prodr. Icldhyol. Scand., p. 117; Bonap. 



(Spinax), Iconogr. Fna Itiil., tab. 139; Sundev., v. We. 



(Squalus), Skand. Fisk., ed 1, p. 187, tab. 40; Jord., 



GlLB., Bull. U. S. Nat Mus., No. 16, p. 16; Lill.i., Sv., 



Norg. Fna, Fisk., vol. Ill, p. 665. 

 Picked Dog Fish, Penn., Brit. Zool. (ed. 1776), vol. Ill, p. 



88; Yare., Brit. Fish., ed. 1, vol. II, p. 400; Coucii, Fish. 



Brit. Isl, vol. I, p. 49, tab. XI. 

 Squalus fernandinus, Molina, Uhili, p. 229; Guichen. (Spiiirix) 



in Gay, Oliile, Zool., torn. II, p. 3S5. 

 Acanthias vulgaris, Risso, Eur. Merid., toni. 3, p. 131; MOll., 



Hle, Plagiost., p. 83; Schleo. in Sied., Fna Japan., Poiss., 



p. 304, tab. CXXXV; Kr., Damn. Fisk., vol. Ill, p. 868; 



Nilss., Skand. Fna, Fisk., p. 731; DOm., Hist. Nat. Poiss. 



(uouv. au. a But?.), torn. 1, p. 437; Barb. Bog. , Cap., Peix. 



Plagiost. Port., p. 21; Gthe. Cat. Brit. Mas., Fish., vol. 



VIII, p. 418; Coll., Forli. Vid. SeUk. Chrnia 1874, Tilla?g.sli., 



p. 211; 1879, No. 1, p. 104; Winth., Naturb. Tidskr. 



Kbhvn, ser. 3, vol. XII, p. 58; Mou., Hist. Nat. Poiss. 



Fr., torn. I, p. 342; Dodeel.. Man. Ittiol. Medit., fasc. II. 



p. 86; M6b., Hcke, Fisch. Osts., p. 152; Day, Fish. Gt. 



Brit., Irel., vol. II, 'p. 315, tab. CLX, fig. 2; Storm, N. 



Vid. Sels. Skr. Trondbj. 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. 232, tab. XXXVIII, fig. 1. 

 Acanthias Linnei, Malm, Ghgs, Boh. Fna, p. 624. 



The Picked Dog-fish belongs to the smaller Sharks. 

 According to Day it attains a length of 12 din. on the 

 English coast; but in Scandinavia it does not exceed, 

 so far as we know, one of about 9 dm.' 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. Tlie greatest depth of the bod}', just in front 

 of the first dorsal fin, varies irregularly bet^\■een about 

 9 and 11 % (according to Khoyer sometimes 8 or 12 %) 

 of its length, the least depth between 2 and 2' ., % 

 (according to Krover sometimes nearly 3 %) of the 

 same. The hitter depth measures between about 13 % 



" .Man. Ittiol. Medit., faac. II, p. 118, Nota. 



' Tliis might besides be taken for granted partly from Rafinessue's description of the teeth of the upper jaw (ilenti mimiti ed acuti), 



pirlly from Barboza de Booaqe's and Capello's iigures of old and young specimens of Centrophorus grtjnii/osiis. 



■" The Vega Expedition brought home a male 9V2 dm. long from Bebring Island. 



