78 REPORT OF NEW JERSEY STATE MUSEUM. 
parts. Nostrils small, nearer angle of mouth than middle of 
nose. Gill-openings obliquely behind angles of mouth, unequal, 
and posterior much smaller. Body smooth. Two elongated 
vertical fins opposite on tail behind spine. Tail a little longer 
than body, thicker and subcompressed at base, attenuated, and 
at point acute. Spine placed nearer base than tip of tail. Fins 
on tail thick, smooth and without distinct rays, elevated in middle 
and gradually sloping towards extremities. Superior fin of tail 
shorter than inferior, arising from near tip of spine, and inferior 
arising near base of spine. Ventral fins rounded, with small 
process near tail. Color olivaceous-red, darker near extremity 
of fins, on upper surface. Lower surface white. Eye brown. 
Fins on tail black. Largest example 18 inches long without tail, 
16 to 17 inches wide, and 4 to 5 inches thick. Bay shore of Egg 
Harbor. (Le Sueur.) 
This does not seem to have been found since Le Sueur’s time. 
Raja say Le Sueur, Journ. Acad. Nat. Sci. Phila., 1817, p. 42. 
Family MYLIOBATID. 
The Eagle Rays. 
Disk broad. Nasal valves forming rectangular flap with pos- 
terior margin free and attached by frenum to upper jaw. Ovo- 
viviparous. Skull less depressed than usual among rays, its sur- 
face raised so that eyes and spiracles are lateral in position. 
Skin smooth. Tail very long, slender, whip-like, with single 
dorsal near its root, behind which is usually a strong retrorsely 
serrated spine. Pectorals ceasing on sides of head and reappear- 
ing in front of snout as 1 or 2 cephalic fins supported by fin rays. 
No differentiated spines on pectorals in males, sexes similar. 
Ventrals not emarginate. 
Large sting rays in warm seas, feeding chiefly on mollusks, 
which they crush with their large grinding teeth. 
Key to the genera. 
a. Muzzle entire. MYLIOBATIS 
aa. Muzzle emarginate; cephalic fins below level of disk. RHINOPTERA 
