474 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



Mylioiatis tenuicauttatis Hector, Trans. New Zealand Inst., vol. 9, pi. 10, figs. 



a-e, 1877. (Error.) 

 Myliobatis tenuicaudaius Waitej, Rec. Canterbury Mus., vol. 1, No. 2, p. 152, pi. 



23, 1909 (off Poverty Bay and Bay of Plenty). 

 MyUo'batis aquila (not Linnaeus) Kent, Great Barrier Reef, p. 103, 1893 



(Elliott Island). 

 Dicerobatis eregoodoo (not Cantor) Kent, Great Barrier Reef, p. 370, 1893 



(part). 



Depth 41/5 to 434 in disk length ; head 2% to 3 ; disk length 11/2 

 to 1^ in its width, 4 in tail. Snout 1% to 2 in head, forms pointed 

 lobe at low level in front ; eye 8 to IOI/2, 4^4 to 5 in snout, &% to 7% 

 in interorbital ; dentary width 3% to 4 in head ; teeth uniserial, lower 

 pavement projecting slightly; lips papillose; nostrils each simple 

 deep slit, internarial 1^4 to 1% in dentary width; interorbital 1% 

 to 1% in head, broad, nearly level or only very slightly convex. 

 Gill openings subequal or last smallest, equidistant. Spiracles large, 

 deep, oblique apertures, twice eye diameter. 



Skin smooth. Caudal spine (single in my specimens) 1% to 1% 

 in interorbital. 



Dorsal length 3% to 4% in head; no anal; tail very long, whip- 

 like; pectoral forms very wide disk, front edges slightly convex 

 and hind edges slightly concave, acute at outer angle; ventral 1% 

 to 1% in head, rather narrow and obtuse or convex terminally. 



Back brown or olive brown. Scattered white, creamy or gray- 

 white spots scattered principally over last half of disk, largest 

 toward middle of disk, and become little more numerous and smaller 

 marginally behind. All spots well contrasted, though ill defined 

 or without sharp borders. Few spots may extend on front of back, 

 on ventrals and base of tail, none on head or greater part of tail. 

 Under surface whitish, outer angles of pectorals marginally little 

 brownish. 



Red Sea, Arabia, Natal, Madagascar, Seychelles, India, Ceylon, 

 Malay Peninsula, Pinang, Singapore, East Indies, Philippines, Co- 

 chin China, China, Queensland, New South Wales, Melanesia, Mi- 

 cronesia, Polynesia, Hawaiian group. A well-marked species 

 known by its uniform or ill-defined white spots chiefly on the pos- 

 terior portion of the disk. These quite variable and sometimes 

 said to be entirely absent. The white spots are not known to ex- 

 tend on the head. As here understood Aetobatis narinari (Euphra- 

 sen) also ranges through the tropical Atlantic and along the American 

 shores in the tropical eastern Pacific. 



4656. Manila Harbor. June 13, 1908. Length, 1,020 mm. 

 8292. Sorsogon market. March 12, 1909. Length, 1,330 mm. 

 9054. Abuyog, Leyte. July 26, 1909. Length, 1,393 mm. 



