14 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



but little arched; a long. deep. straight, oblique groove on each side of 

 il : spiracle- present. (Tin- alienee of dorsal .spines chielly distinguishes 

 this family from Sjiliniritltr.) 



(lenera six: species six or more, mostly of the Atlantic. (Giiuther, 

 X]>!iia<'!<l<r. pt. viii, li'.'i- li'O.) 



" I'ir-t dcir-al ii]i]io-;iir vrntrals: irrth equal in both jaws, very oblique ; skin ron^h 

 \\ i ill till invles and prirkles ............................... Ecin\< nan NTS, 8. 



' i'ir-t ilorsnl iiinrli in ailvaiirr of ventral-- : tin- d<>r>als a)>mil equal: ii|i|n-r in-tli 

 narrow: lower <|ii;!ilralr, with a hori/onlal ed^e ending i" :i point directed 

 mi i wards .................................................... .SoMNiusus, 9. 



8. ECIIIXORIIINUS Blainville, 1616. 



Spinons Sharks. 

 (Gtniodua Agassiz.) 

 (Blainvillr, 1816; tyjir >.///<[// spinosits Gmelin.) 



T\vo very small dorsal fins without spine, the first opposite the ven- 

 trals: no anal fins; skin with scattered large round tubercles, sur- 

 mounted by prickles, like those on a bramble, and, like them, leaving n 

 scar when detached. Mouth crescent-shaped, a la bial fold around the 

 angle of the mouth ; nostrils midway between the mouth and the end of 

 the snout. Teeth equal in both jaws, very oblique, the point Iteing 

 turned outwards; several strong dent iculat ions on each side of the 

 principal point. Xo nictitating membrane. Spiracles small ; gill-open- 

 ings of moderate width. A single species of the East Atlantic, straying 

 to our co;t.-,t. (i-/~.v<>-, :i hedgehog, or sea-urchin ; {>^f n shark.) 



I :t. t. spiiiosus (Omcl.) I'.lainv. Xpinottx Shark; Jloinh'. 



"Spiracles behind the eye, behind the vertical from the angle of the. 

 mouth. Teeth :;^:|:. Dorsal fins close together. Each tubercle with a 



small sjiine in the centre. P.nnvnish violet, with or without dark spots'' 

 <: intlu-r}. A large shark of the coasts of Europe and Africa ; a stray 

 individual lately taken on Cape Cod. 



limrlin I. inn. 1, l.~>ni); (Jiinthrr, viii, I.-*.) 



O.~SO.1I\IOSUS Le Sm-nr, HIS. 



i HKirilUH Miillrl" iV Ilrnlr.) 



I 3aeUT, .Jmn. \<\ \al. Sri. I'liil.-i. l-l-. i, 'J.'-J ; ty]ir. ^i 

 Slirli] Si/milii* mil i-'ni /ilnilux I'.locll.) 



I'.ody elongate : mouth Irausvei'sc, lit tie arched, with a deep straight 



>\e ninning ba<-kward I'rom itsan-le: nost rils near t lie e\t I'emity of 



the. snout ; jaws feeble; teeth in upper jaw small, narrow, conical; lower 



