450 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



Pteroplatea Muixeb and Henle, Sitz. Ber. Akad. Wiss. Berlin, 1837, p. 117. 



(Atypic.) (Type, Raja altavela Linnaeus, virtually affixed by Jordan and 



Gilbert, U. S. Nat. Mus., Bull. 16, p. 46, 1883.) 

 Planerocephalus Gbatzianow, Zool. Anz., 1906, pp. 400, 403. (Type, Planero- 



ccphalus elliott Gratzianow=i2oia mici^ura Schneider, monotypic.) 



(Monstrosity.) 



Disk much wider than long, lozenge shaped, angles rounded, de- 

 pressed and thin. Tail short, slender, with )or without narrow 

 dermal folds behind serrated spine. Head not prominent. Eyes 

 small, prominent. Mouth wide, transverse, little arched; jaws 

 slender. Teeth minute, numerous, in broad band, each tooth with 

 wide base, with 1 to 3 sharp cusps. Nostrils wide, separated by 

 broad isthmus; front valves confluent, crossing isthmus as narrow 

 fold; posterior valves rudimentary. Spiracles large, close behind 

 eyes. No dorsal fin. Pectorals wide, meeting in front of head. 

 Ventrals small, narrow. 



Temperate and tropical seas. 



ANALYSIS OF SPECIES 



a\ AETTOPiiATEiA. Usually small dorsal fin at base of tail before caudal spine. 



b^. Tentacle behind spiracle; tail less than half of body tentaculata 



&^ No tentacle behind spiracle ; tail about half as long as body zonura 



o'. Gymnxjba. No dorsal fin. 



c\ Tail nearly long as body poecilura 



(f. Tail half long as body, 

 d*. Chin without 2 denticles. 



e\ Uniform brown above japonica 



e^ Two large white blotches above bimaculata 



(^^ Chin with pair of wide-set denticles crooki 



c'. Tail less than half long as body micrura 



Subgenus Aetoplatea Valenciennes 



GYMNURA TENTACULATA (Muller and Henle) 



Aetoplatea tentaculata (Valenciennes) MtixLER and Henle, Syst. Beschr. Plagi- 

 ostomen, p. 175, 1841 (type locality: Red Sea, Malabar). — Bleeker, Verb. 

 Batav. Genootsch. (Bengal), vol. 25, p. 82, 1853 (reference). — DuMfiRH,, 

 Hist. Nat. Elasmobr., vol. 1, p. 630, 1865 (types). — Gasman, Mem. Mus. 

 Comp. Zool., vol. 36, p. 411, 1913 (Red Sea, Indian Ocean, Malabar). 



Pteroplatea tentaculata Gunthee, Cat. Fish. Brit. Mus., vol. 8, p. 488, 1870 

 (copied). — Annandale, Mem. Indian Mus., vol. 2, p. 40, pi. 4, fig. 4, 1909 

 (off Hughli River mouth, Orissa and Ganjam coasts, in 15-30 fathoms). 



Pteroplatea australis Ramsay and Ogilby, Proc. Linn. Soc. New South Wales, 

 vol. 10, p. 575, 1885 (type locality: Cape Hawke, New South Wales). — 

 Ogii^y, Proc. Linn. Soc. New South Wales, vol. 10, p. 466, 1885 (no des- 

 cription) ; Cat. Fishes Australian Mus., pt. 1, p. 22, 1888 (type; Broken 

 Bay) ; Ann. Queensland Mus., No. 9, p. 5, 1908 (Moreton Bay) ; Mem. 

 Queensland Mus., vol. 5, p. 88, 1916 (Moreton Bay, off Port Curtis and Cape 

 Gloucester, 14-25 fathoms; note). — McCtjlloch, Australian Zool., vol. 1, 

 pt. 4, p. 89, pi. 1, fig. 3, 1917 (Tuggerah Lakes, New South Wales).— 



