464 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



Skin smooth. Caudal spine long as head. 



Dorsal length 3 in head; no anal; tail long, slender, whiplike; 

 pectorals broad, front edge entire, hind edge little concave, angles 

 rather obtuse; ventrals broad, obtuse, rather short; claspers flattened, 

 conic, ends blunt, each with 2 deep lateral grooves, length 1% in head. 



Back uniform brown, little paler about edges of disk. Tail dusky. 

 Under surface of body whitish. 



China, Japan, Korea. None of my specimens show any lighter or 

 paler spots. 



U.S.N.M. No. 8067. Nippon. William Stimpson. Length, 575 mm. 



U.S.N.M. No. 22611. Miuramisaki, Japan. Imperial Government of Japan. 



Length, 565 mm. 

 U.S.N.M. No. 49409. Yokohama, Japan. Albatross collection. Length, 565 mm. 

 U.S.N.M. No. 51297. Nagasaki, Japan. Albatross collection. Length, 260 mm. 



to end of cut off tail. 

 U.S.N.M. No. 75866. Japan ? P. L. Jouy. Length, 585 mm. 

 U.S.N.M. No. 75867. Japan ? P. L. Jouy. Length, 550 mm. 

 U.S.N.M. No. 75868. Japan ? P. L. Jouy Length, 485 mm. 



Genus AETOMYLUS Garman 



Aetomylus Gaeman, Bull. Mus. Comp. Zool., vol. 51, p. 252, 1908. (Type, Mylio- 



batis maculatus Gray, orthotypic.) 

 Aetomyleus Sharp, Zool. Record, No. 44, 1908, index, p. 1, 1910. (Type, Mylio- 



batis maculatus Gray.) 

 AetomylcBus Gaeman, Mem. Mus. Comp. Zool., vol. 36, p. 434, 1913. (Type, Mylio- 



batis maculatus Gray.) 



Disk broad. Tail without caudal spine. Head moderately con- 

 spicuous. Teeth with 3 narrow lateral rows each side of wide median 

 row. Rostral fins not continuous with pectorals at side of head, 

 placed on lower level and united in one lobe. 



ANALYSIS OF SPECIES 



o'. Dorsal origin behind ends of ventral bases. 



&\ Back with median small spines and tubercles ; brovpn-edged ocelli on hind 



part of disk maculatus 



6'. Back smooth ; brownish with network of black, anteriorly in bands. 



vespertilio 

 o^ Dorsal origin opposite ends of ventral bases. 



c^. Disk less twice wide as long; green brown-edged ocelli on hind part of 



disk milvus 



c*. Disk twice wide as long ; about 5 blue cross bands, disappearing with age. 



nichofii 

 AETOMYLUS MACULATUS (Gray) 



Myliobatis maculatus Gray, Ulustr. Indian Zool., Hardwicke, vol. 2, pi. 101, 

 1832-34 (type locality: Pinang). — Mxjxler and Henle, Syst. Beschr. Plagi- 

 ostomen, p. 178, 1841 (India). — Gray, List fish British Museum, p. 129, 

 1851 (no locality). — Bleeker, Verb. Batav. Genootsch. (Plagiost.), vol. 

 24, p. 84, 1852 (Batavia, Samarang, Pasuruan) ; (Bengal), vol. 25, p. 82, 

 1853 (reference) ; Act. Soc. Sci. Indo-N6erl., vol. 5, no. 7, p. 2, 1859 (Sinka- 



