34 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY - IV. 



FAMILY XV. HEXANCHID.E. 



(The Coic SJiarlcs.) 



Body elongated, somewhat depressed anteriorly, tapering towards the 

 caudal tin. Head depressed, oblong and semi-oval or semi-elliptical 

 above, with the snout projecting. Eyes submediau or anterior, without 

 nictitating membranes. Mouth inferior, large, arched in front, no labial 

 fold. Teeth in the two jaws unlike; in the upper jaw one or two pairs 

 of awl-sliaped teeth, the next six teeth broader, and each provided with 

 several cusps, one of which is much the strongest. Lower jaw with six 

 large comb-like teeth on each side, besides the smaller posterior teeth. 

 Spiracles small, on the side of the neck. Only one dorwilfin, /ritltout xpine, 

 opposite the anal, and similar to it. Xo pit at the rootjof the caudal tin. 

 Gill-openings wide, nix or seven in number. Genera U ; species 4 or 

 more; mostly of the Eastern Atlantic. (Notidamd(e Giinther, viii, 397- 

 399.) 



* Grill-openings seven on each side .................................. HEPTANCl'S, 32. 



32. HEPTANCUS Ralmesque, 110. 



Perlons. 







CNotidanim Cuvier, 1817.) 



(Hcptranchias Rafmesque, Caratteri di Alcuni Nuovi Generi, etc.: type Xqualus 

 (increux Gmelin.) 



Characters same as those of the family with the addition of gill-open- 

 ings semi, which separates this genus from Hcxancus. ('/, seven; 

 7, bend or sinus, for gill-opening.) 



'Median tooth of lower jaw without, central cusp. ( .\iilorhynctinn Ayrcs.) 



42. II. imlicus (Cuvier) Miiller \- 1 1. Mile. 



" Snout short and rounded ; cleft of the mouth broadt'r than long. A 

 single median pointed tooth in the upper jaw; the lower median tooth 

 with lateral cusps, but without central cusp. The lirst cusp of the lower 

 teeth is much stronger I ha nt he others and serrated on its outer margin." 

 ((iiinfln-f.) Dark bluish gray, with many small irregular black Itlotches. 

 Tail more than one third of total length. Si/e large. Cape of Good 

 Hope to California : not rare ;it San Francisco. 



t \oliildiinn MldiCiM Cuvier, li'c-^m- Animal: NotidaiHU i/RtKout (iiinther, viii, lilt--: Xolo- 

 rhym'liiiH niiifiilnliiK As n->. I'mc. C;il. \ai. S-i. i, ?_' : .\utdiii i/nchii^ mdcnlniitu Gill, Proc. 

 Ac. X;ii. Sci. 1'liila.. l-ti'J. I'.i:.. .-Mi.l l^C.l, M'.: Xotui-liynclius boreiilis Gill, Proc. Ac. Nat. 

 Sci. Phila. iHil, ir.ti. 



