328 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



Head to hind spiracle edge 5% in total length. Snout I14 in head 

 to hind spiracle edge; orbit 5%, ^Vi in snout, I14 in interorbital ; 

 mouth width 2% in head to first gill opening; teeth very small; 

 nostrils short, each 2l^ in internasal, which 3i^ in head to first gill 

 opening; front valves continuous across internarial space, hind valve 

 with inner flap wide as combined outer flap and lobe, extend near 

 though not quite to mouth angle; interorbital 3i/4 in head to hind 

 spiracle edge. Spiracles entire, close behind orbit and 1% in orbit. 



Scales variably minute or larger. Small tubercles above rostral 

 cartilages, orbital ridges, basal pectoral cartilages and entire vertebral 

 series to dorsal. 



First dorsal origin about midway between hind ventral ends and 

 second dorsal origin, fin 214 in head to hind spiracle edge; second 

 dorsal 2% I caudal 1%, no subcaudal lobe, fin rounded ; pectorals form 

 subcircular disk with blunt snout tip in front, length 1% in rest of 

 body, IVe in its width ; ventrals obtuse. 



Above and below brown, upper surfaces with darker transverse 

 bands and between toward pectoral edges scattered dark spots. Be- 

 low body with irregular large dark blotches. (MiJller and Henle.) 



India. Also reported from "West Africa by Steindachner. His 

 specimen was about 400 mm. long and according to his figure is a 

 little differently marked, the dark blotches on the pectorals greatly 

 larger toward bases of fins and tail with broad dark bands bordered 

 with smaller ones. Dumeril gives 473 mm. length for the specimen 

 in the Berlin Museum. 



Genus PLATYRHINA Muller and Henle 



Platyrhina Muixeb and Henle, Mag. Nat. Hist., vol. 2, p. 90, 1838; Beschr. 



Plagiostomen, p. 125, 1841. (Type, Rhiva sinensis Schneider, selected by 



Bonaparte, Ann. Sci. Nat., Bologna, vol. 2, p. 205, 1838.) (Platyrhinus 



Schellenberg 1798 not involved.) 

 Narcopterus Agassiz, Poissons fossiles, vol. 3, p. 382, 1843. (Type, Narcopterus 



ftoZcantts Agassiz, monotypic. No description. ) (Fossil.) 

 Analithis Gistel, Naturg. Thierreichs, p. x, 1848. (Type, Rhina sinensis 



Schneider, virtually. Analithis Gistel proposed to replace Platyrhina 



Miiller and Henle.) 



Disk subcircular to subtriangular, with broadly rounded angles. 

 Tail slender, about half total length. Kostral cartilages short, wide, 

 not extended half space from skull to snout end, truncate and sup- 

 plemented by soft prolongations, somewhat as in Torpedo. Eyes 

 small. Nostrils nearly transverse, connected with mouth by deep 

 groove; front narial valves extended upon but not crossing inter- 

 narial space. Spiracles close to eyes, with cartilage each side, with- 

 out folds. Dorsals far behind ventrals, small, rounded. Caudals 

 about equal, truncate; subcaudal not lobed. Pectorals very wide, 



