DISCUSSION OF SPECIES AND THEIR DISTRIIUJTION. • 9 



Echinorliiiius splnomis, Ulaivville, Bull. Sti., 1816, 121.— Fanne Frauvaise, 6G.— Bonaparte, Icon. Fauu. 



Ital., Pesci, III, pi. cxxxviii. — Mullek and Hknle, S. B. I'lag., 96, \>\. i.x.^Yakuei.i,, Brit. Fi.sh., 2<1 ed.. 



n, 532, fig. ; 3il eil., li, .'529.— Costa, Fauna, Nap. Clioud., XM.— DlJil^ntiL, Iditliytdogie, I, 459.— GCxriiKi:. 



Cat. Fish. Brit. Mus., viii, 428. — Goode and Beax, Bull. Essex Institute, 1877, 31.— Caxestkixi, 



Fauna Italica, Pesci, 42.— .Ioudax, loc. cit., 13. — Giglioli, Pcsci Italici, Cat., .")3; Elenco, 1883, 113.— Day. 



Fishes Gt. Brit. & Ireland, ii, 323, pi. ci.xii, fig. 2. 

 Goniodiis sjnuosim, Agassiz, Poi.ss. Foss., in, pi. E, fig. 13. 

 CinlroplKinis spiiioiius, Swaix.so.n, Fishes, ii, 315. 

 S(iiu(his hniciis:, BoXN'ATEiiiiE, Eneyclopt'-die Mi^thodique. 

 Efhiiioi-hhniii oheKKx, S.MITII, lllustratiiins of the ZoJilogy of Siiutli Africa. 1838-42, Pisces, pi. i. 



Spiracles hehiud the (\ve, behind tlie vertical from the angle of the month. Teeth 

 2|^. Dor.sal fins close together. Each tubercle with a small spine in the center. Brownish 

 violet, with or without dark spots. (Gilnther.) 



A single iiidividaal has been observed in the western Atlantic. Tiiis drifted ashore at 

 Provincetowu in December, 1S7S (Uoode and Bean, loc. cit.). In the ^Mediterranean it israre, 

 and lives at considerable depths (Oanestrini, Fauna d' Italia, Pesci, p. 42). Eis.so men- 

 tions one weighing 400 jiounds. Day records the occurrence of some thirty individuals in 

 liritish waters sincii 1S2S, tiie largest 9 feet in length; tlii.s was a female and contained 

 seventeen eggs, and was taken off the Eddystone in January, ISGO. Since captures in this 

 region luive been made at all seasons of the year, it would appear that its breeding place 

 and home is in the northeastern Atlantic, and that its infrequent capture is due to its habit 

 of living on theoffsiiore ledges and banks at considerable deptlis. As the synonymy shows, 

 it was recorded by Smitli from the (Jape of Good Hope. It may be regarded as peculiar to 

 the eastern part of the Atlantic Basin, the Cape Cod specimen being dovibtless a waif. 



Family SQUALID^^, Gunther. 



Spinacidce, Gunther, Cat. Fish. Brit. Mus., viii, 1870, 417-125.— .loiaiAX anii (iiLiiKijT, liull, xvi, U. S.Nat. 

 Mus., 1883, 15. 



Selachians witli body somewhat elongate and head depressed; eyes lateral; nictitating 

 membrane absent; inoutii inferior, rather large, with a deep groove along either side; teeth 

 compressed, varied; nostrils inferior, lateral, near the front margin of the snout; spiracles 

 moderate; gill openings moderate, Ave on each side and all in ft-ont of the pectoral fins; 

 dorsal tins two, each armed with a spine; the first dorsal in front of the i)ectorals; anal fin 

 lacking; caudal fin with the h)wer lobe small or obsolete; ventrals far back. 



Of the seven genera com])rising this family only two, Squalus {=Aeanthias) and Ory- 

 natus ( = Gc)itriit<i), are shallow water forms. Of the.se, all the species are reiu'eseuted in 

 the Mediterranean. Tlie family Spinaridw is peculiarly characteristic of the Mediterranean 

 fauna, all known species except three, one of which is from the northwestern Atlantic and 

 two are from Japan, occurring in that sea or wateis immediately adjacent. <SV/»r(/».s is the 

 most cosmopolitan of the genera, hut does not enter the North I'acilic. 



The deep-sea forms of these little sharks are especially abundant in the great depths 

 outside the entrance to the Mediterranean, where an extensive fishery is carried on. 



KEY TO THE GENERA OF SPINACIDvK. 



(Adapted from Vaillant.) 



I. Trunk more or less rounded. 



A. Upper teeth hicuspid. 



1. Lower teeth ol)li(iue, with trenchant inner edges Etmopterus 



2. Lower teeth tricuspid Ci:nti!.)scyi,i.hm 



B. Upper teeth oblique, with trenchant inner cdj;es; lower teeth similar. .. [Scjiai.cs. — Shallow water.] 



C. Upper teeth simple, iiointed. 



1. Lower teeth more or less en^ct, triangular ScVJfNODON 



2. Lower teeth oblique, with trenchant inner edges. 



a. Dorsal spines prominent ; " npper teeth triangular," Vaillant CextropiiorU8 



b. Dorsal .spines hidden ; "upper teeth conical," Vaillant Cextuoscymnos 



3. Lower teeth simple, straight Paracicntro.scvixiu.m" 



II. Trunk rather elevated, trihedral. Teeth erect, conical in upper jaw; trianirular, .serrated iu lower jaw. 



OXYNOTnS 



* A deep-sea genus from the Bay of Bengal, described byAlcockin Ann. and Mag. Nat. Hist., 1889, 379. 



