1149 



THE BLACK-MOUTHED DOG-FISH (sw. hagalen). 

 PinsTHKrs (ATULUS. 



Plate LI, fig. 2. 



Coloration ahovc of a rcddisli ar ijroiniish ijrai/, with spots darker than the ground-roloar Iml vith a liqhter 

 border, and varying in size and form, nsuaUy larger, quadrangular or rounded, next the hack, smaller down the sides. 

 Dorsal fins behind, the other mipaired fins at the base more or less cinereous, at the tops darker. Pectoral and 

 ventral fins of the same colour as the hack or sides, hut immaculate, pcding outwards. Ventral side white. Mouth 

 and pharynx, as well as the branchial cavity and peritoneum, black. Iris light blue. 



&'>/n. Haae-Gicgle, Stb5m, Sondm. Beskviv., part. I, p. 283. 



Squalus Uatutus (Haae-Gwlen), Gunner., Troudh. Selsk. Skr., 

 vol. II, p. 235; Asc.\N. (Rodhaae), Icon. Rer. Nat., tab. 

 XXXVIII; Risso, Ichth. Nice. p. 30 (p. p.; femiuam Scyllio- 

 rhini caniculce credidit); LiLL.1. (Pristiuriis), Sv., Norg. Fna, 

 Fish, vol. Ill, p. 657. 



Galeiis melastomns, Rafin., Caratteri N. Gen., N. Sjk, p. 13; 

 Yarr., Brit. Fif/i., vol. II, ed. 1, p. 375 {Scyllimn), ed. 

 2, p. 495 (Pfistiiinis); Bonap. {Prisliurus tnelatiostomtis), 

 Fna Ital., Pesri. tab. 131, fig. 3; MUll., Hle, Plagiost., 

 p. 15, tab. 7; Lowe, Fish. Madeira, p. 93, tab. XIV; 

 Kr. {Scylliuin melastomum), Danm. Fisk., vol. Ill, p. 832; 

 Gthr (^Pristiuriis melanostomus), Cat. Brit. Mus., Fish... vol. 

 VIII, p. 406; Coll., Forh. Vid. Sels. Chrnia 1874, Till.-Bgsh., 

 p. 211; N. Mag. Naturv., Bd 29 (1884), p. 117; Malm, 

 Gbgs, Boh. Fna, p. 623; Winth., Naturh. Tidskr. Kbhvn, 

 ser. 3, vol. XII, p. 58; MoR., Hist. Nat. Poiss. Fr., toin. 

 I, p. 284; Day, Fish. Gt. Brit., Irel, vol. II, p. 314, 

 tab. CLX, fig. 1; Storm, N. Vid. Sels. Skr. 1883, Trondlij., 

 p. 43. 



Scyllium Artedi, Risso, Euv. Merid., torn. Ill, p. 117; Barb. 

 Boo., Cap. {Pristiunts), Pei.t. Plagiost., p. 11. 



Squalus annulatus. Nilss., Prodr. Ichtliyol. Scand., p. 114; 

 {Scyllirm), Skand. Fna, Fish., p. 713. 



The Black-mouthed Dog-fish attains according to 

 Stoum a length of 80 cm., according to Moreau of 90 

 cm.; but it is commonly smaller. Our specimens from 

 Scandinavia measure between 33 and 68 cm. The largest 

 are females. The body is of the elongated Shark-form, 

 with flattened snout, more terete, though somewhat de- 

 pressed head, behind which the vertical section is more 

 or less triangular (hog-backed), and more or less com- 

 pressed tail, almost flattened on tlic sides, the depth 

 just in front of the caudal fln being about twice the 

 thickness. The greatest depth, at the pectoral fins, is 

 in the males about 9 %, in the females about 10' o %, 

 of the length of the body. The greatest breadth falls 

 within the head, just in front of the fir.st brancliial 

 aperture, and varies, as usual, with the di.stension of 

 the jaws and branchial apertures, being somewhat less 



Fig. 334. Ventral side of a Black-mouthed Dog-fisli (Pristiitrus ca- 



tulus), $, from the fishing-bank of Jaderen. Nat. size. The anterior 



outer lobe (lae) of the right nostril is raised to show the anterior 



inner (/</)') and the posterior outer (Ipe) lobes. 



or greater than the greatest depth. The least depth 

 of the tail, just in front of the caudal fin. is about 

 4 — 4'/, % of the length of the body. 



