22. MYLIOBATID,E RHINOPTERA. * 51 



67. M. fa'cmaBBviiBIei Le Sueur. 



Disk broader than long, the breadth equal to the length of the tail. 

 Skin entirely smooth. A blunt, whitish prominence over each eye. 

 Muzzle prominent. Teeth of the main row 4 to G times broader than 

 long ; small teeth in three rows. Eeddish brown. Tail nearly black. 

 Cape Cod to Brazil ; not uncommon. 



(Le Sneur, Journ. Ac. Nat. Sci. Phila. iv, 111 : Myliobatis Uspinosus Dume"ril, Hist. 

 Nat. Poiss. 637: Myliobatis acnta Storer, Hist. Fish. Mass. 2-15.) 



68. M. caIifB*BBi<CMS Grill. California Sting Ray; Batjtsh. 



Disk not quite twice as broad as long ; the wings anteriorly convex, pos- 

 teriorly somewhat concave. Cephalic fin very blunt, nearly 4 times as 

 broad as long. Tail nearly twice as long as the disk. Ventral large, 

 broader than long. Lateral teeth in 3 to 5 series on each side ; median 

 teeth only 3 to 4 times as broad as long, even in the adult. Skin wholly 

 smooth. Color dusky brownish, the young somewhat variegated. San 

 Francisco southward; very common on the Pacific coast. 



(Rltinoptcra vcspertilio Girard, Boston Journ. Nat. Hist. 1857, 544: HolorMnus vesper- 

 lilio Gill, Proc. Acad. Nat. Sci. Phila. 1802, 331 (not Myllobatis vespertiUo Bleeker); 

 Gill, Ann. Lye. Nat. Hist. N. Y. 1885, viii, 137.) 



43. RHINOPTERA Kuhl. 

 Cow-nosed Rays. 



(Kuhl, Miiller, Abhaudlungen Ak. Wiss. Berl. 1836, 237 : type Rhinoptera brasiliensis 

 Miiller = Myliotatis jussieui Cuvier.) 



Disk broader than long, with the anterior angles more or less acute. 

 Snout more or less emarginate on the median line. Cephalic fin emar- 

 ginate and placed on a plane below the level of the pectorals, the snout 

 thus appearing four-lobed. Free border of the nasal valve not emar- 

 ginate. Teeth in 3 to 20 rows, the median teeth more or less enlarged, 

 but often smaller than in Myliobatis. Tail long, whip-like, with a small 

 dorsal fin and" a serrated spine. Tropical seas, (fa, snout j -rspov, fin.) 



69. R. qiQf&driloba, (Le Sueur) Cuvier. 



Disk one- third broader than long; anterior borders almost straight, 

 posterior undulated ; muzzle deeply emarginate. Teeth in seven rows, 

 the median teeth four times as broad as long. Tail very slender, a lit- 

 tle longer than the disk. Skin smooth or nearly so. Color brownish. 

 Cape Cod to Florida ; not rare. Attains a large size. 



(Raia qnadriloba Le Sueur, Journ. Ac. Nat. Sci. i, 44; Giinther, viii, 494; Dum6ril, 

 Hist. Nat. Poiss. i, 648. 



