Bulletin 47, United States National Museum. 



Family VIII. SCYLLIORHINID^. 

 (THE CAT SHARKS.) 



Dorsal fins 2; both rather small, without spines, the first more or less 

 behind the ventrals; anal fin present, usually before the second dorsal; 

 caudal fin rather long, usually with a basal lobe; the tail not keeled, and 

 not bent upward. Spiracles present; no nictitating membrane; gill open- 

 ings small, the last one above the root of the pectorals. Mouth usually 

 broad, with small teeth, several series being in function ; teeth each with a 

 median cusp and 1 to 4 small cusps on each side ; nostrils near the mouth, 

 sometimes confluent with it, sometimes provided with cirri. Mucous pores 

 about head numerous, especially on lower side of snout. Egg cases large, 

 quadrate, with prehensile tubes at the angles. (SCYLLIID^E, Giinther, Cat., 

 vm, 400-413.) 



a. SCYLLIORHININ^E. Spiracles close behind eye; gill openings nearly equidistant; teeth small, 



usually tricuspid. 

 b. Nostrils not separated by an isthmus, the nasal valves confluent ; tail not serrated. 



SCYLLIORHINUS, 14. 



bb. Nostrils separated from each other by a broad isthmus. 



c. Scales on upper margin of the tail little if at all enlarged, usually similar to those 

 on rest of body, or at any rate not forming a serrated edge. CATULUS, 15. 



14. SCYLLIORHINUS, Blainville. 



(ROUSSETTES.) 



Scylliorhinm, Blainville, Journ.Phys.181C, 263 : (canicula, etc.). 



Scyllium, Cuvier, Regne Animal, Ed. 1, 1817, 124, (canicula}. 



Scylliorhinm, Gill, Ann. Lye. Nat. Hist. N. Y., 1861, 41, reprint, (restriction to canicula). 



This genus includes those Scyllioid sharks in which the nasal valves 

 are confluent, with their hinder border entire and free. Caudal moderate ; 

 gill openings equidistant ; spiracles close behind eyes ; tail not serrated. 

 Species mostly of the old world. (aitvMdov, a small shark; OKVA^CJ, to tear ; 

 fiivij, shark.) 



22. SCYLLIORHINUS PROFUNDORUM, Goode & Bean. 



Nasal valves confluent, with a short blunt cirrus on the posterior as 

 well as on the anterior flap ; length of nasal cavity about equal to hori- 

 zontal diameter of the eye, the 2 cavities separated by a space equal 

 to i interorbital area and f- snout; distance of posterior angle of nasal 

 cavity from root of teeth at nearest point i area between cavities ; 

 distance from symphysis to tip of snout equal to width between angles 

 of mouth. A well-developed labial fold at angle of mouth, extend- 

 ing on lower jaw halfway from its angle to the symphysis, and on 

 upper jaw nearly in direction of nasal cavity, disappearing at i the 

 distance. Teeth moderate, with 2 small lateral cusps on each side of the 

 longer middle cusp, in about 5 rows. Gill openings narrow, some- 

 what less than long diameter of eye; distance from first to last, which, 

 like the fourth, is above angle of pectoral, equal to i snout. Ventral 

 fins thick, short, leaf-shaped, their origin twice as far from nasal cavity 

 as is last of gill openings; origin of anal under tip of first dorsal, its end 



