DISCISSION OP SPECIES AND THEIR DISTRIBUTION. 15 



Dr. E. Percival Wrighl reported to Dr. G-unther that he had seen the Portuguese fish- 

 ermen capturing this form at a depth of 400 or 500 fathoms, with hand lines 2,400 feet in 

 length, and that they came from the same depth with Hyalonema. 



Gentroscymnus obscurus, Vaillant (Voy. Travailleur e1 Talisman, 67, pi. n. fig. 2), is 

 doubtfully assigned to this genus, having close affinities also with Centrophorus. It was 

 taken off Soudan in 200 fathoms and below. 



OXYNOTUS, Rafinesque. 



Oxynotut, Rafinesque, Indice, 1810, r>. 



f.nii i mi. Cm ier) Regne Animal, ed, 1, 1817, n, 130. 



Spinacoid sharks, with elevated, trihedral trunk, and with a fold of skin along each 

 abdominal edge, and upon dorsal ridges between the fins; two dorsal fins, each with strong 

 spine; no anal. Mouth narrow, with deep lateral grooves. Lower teeth small, erect, trian- 

 gular, serrated; upper teeth slender, conical, grouped in front of Jaw. Spiracles wide, im- 

 mediately behind eye. Branchial openings narrow. No nictitating membrane. 



Mediterranean and adjacent parts of Atlantic. 



OXYNOTUS CENTRINA,(Linn.), Rafinesque. (Figure 21.) 



Squalus centrina, Linnaeus, Syst. Nat., ed. x. 1758, 1, 233 (from Mediterranean, based on descriptions of 



Rondelet and Salviaui). 

 Oxynotus oentrina, Rafinesque, [nd. A' Ittiologia Sieiliana, 1810, 15,60. — Gill, Ann. Lye. Nat. Hist. N. Y., 



' vii. 405. 

 Squalus ( deanthorhinus) oentrina, Blainville, Faune Franeaise, 61, pi. \\ . tig. 1. 



Centrina Salviani, Risso, Hist. Nat. Eur. Mend., Poiss., in, 135. — Bonaparte, Icon. Faun. Ital., Pesci, cxli, 

 fig. 2. — MCllek unci Hi:m,k. s. B. Plag., 87. — Bocage and Capeli.o, Peixes Plagiost., 32. — Capello, Joru. 

 Acad. Sci. Lisboa, n. 142, fig. of teeth. — Gunther, Cat. Fish. Brit. Mus., vni, 417.— Canestrini, Pesci 

 d' Italia, 41.— GuiCHENOT, Explor. S.i. d' Algeria, Poissons,126.— Day, Fish. (i. B. & Ireland, II, 318.— 

 GlGLlOLl, Elenco, 1883, 112. 



Centrina oxynotus, Swainson, Fishes, ti, 365. 



Centrina vulpecula, Moreau, Poiss. de la France, i, 355, Hg. 61. 



The Centrina, called in Italy " pesce-porco," u puerco" and "pourc-marm," in Por- 

 tugal " peixe-porco„' n in France •• humantin,,'" is not unusual in the Mediterranean, and indi- 

 viduals have been taken at considerable depths on the Setubal banks, by Portuguese natural- 

 ists, while Moreau records a straggler from the mouth of the Loire. In 1*77 one was taken 

 in 2(3 fathoms off the coast of Cornwall, and in past years the species appears to have strayed 

 as far north as Cornwall. 



Its claim to a position among the dee]) sea lishes is doubtful, but in the opinion of some 

 ichthyologists it is an inhabitant of great depths. 



It has never been found outside of the northwest Atlantic. 



Family SCYLLIORHINID^E. 



Scylliidce, GOnthkr, Cat. Fish. Brit. Mus.. vni, 1870, 400. — Gill, Fam. Fishes, 24. — Day. Fishes (it. Britain 

 & Ireland, n, 309. 



A family of sharks distinguished by the position of their dorsal fins and their laying- 

 eggs like those of tin' rays. The body is more elongated than in the sharks generally; the 

 scales developed, as fine shagreen; the head depressed and oval: the nostrils with large flaps; 

 the mouth inferior and arched ; the teeth small (several series being in use at the same time), 

 compressed, and cuspidate; branchial apertures five, the posterior of which are above the 

 pectorals; spiracles behind the eyes well developed; dorsal tins two, the anterior above or 

 behind the ventrals; anal fin present, variable in position ; caudal tin extended toward the 

 end of the tail, and with the lower lobe little produced downward at its front margin: pec- 

 torals moderately developed and with rounded angles. 



