Fishes of the Western North Atlantic 199 



or part way to the latter. Although this group includes only three known species," our own 

 examination of specimens in the collection of the Museum of Comparative Zoology satis- 

 fies us that Carman's" reference of them to his two new genera, Haploblepharus and Ate- 

 lomycterus, was justified by the sharp differences summarized in the following key. 



Key to Genera 

 la. Only one dorsal fin. Pentanchus Smith and Radcliffe, 1912. 



Philippines, Japan. 



lb. Two dorsal fins. 



2a. Origin of ist dorsal considerably anterior to origin of pelvicsj rear contours of 

 dorsal fins straight or concave. Cephalurus Bigelow and Schroeder, 1 94 1 . 



Gulf of California and Revillagigedo Islands, oflF 

 west coast of Mexico. 

 2b. Origin of ist dorsal over, or usually behind, origin of pelvics. 



3a. Denticles along dorsal margin of anterior part of caudal enlarged and modi- 

 fied in shape, forming a distinct crest, outlined below by a narrow band of 

 naked skin. 



4a. Nostrils far from mouth, the distance from their inner angles to corners 

 of latter about V2 as great as horizontal diameter of eyej posterior mar- 

 gin of nostril not lobed; snout long, thin, its mucous pores not conspicu- 

 ous. Galeus Rafinesque, 18 10, p. 214. 

 4b. Nostrils close to mouth, although entirely separate from latter j distance 

 from inner angle of nostril to corner of mouth not more than V4 as great 

 as horizontal diameter of eyej posterior margin of nostril with a well 

 developed lobe j snout short and thick, its mucous pores very prominent. 



Parmaturus Garman, 1906. 



California, Japan. 



3b. Denticles along dorsal margin of anterior part of caudal similar to those 

 lower down, not forming a distinct crest. 



5a. Anterior margin of nostril bilobed, the outer lobe in the form of a fleshy 

 barbel reaching to mouth (Fig. 31). Conoporoderma Fowler, 1934. 



S. Africa, Natal, Mauritius. 



5b. Anterior margin of nostril little or not at all bilobed j without well de- 

 veloped barbel. 

 6a. A well developed labial furrow on lower jaw, but not around corner 



of mouth or on upper jaw. Scyliorhinus Blainville, 1 8 1 6, p. 202. 

 6b. Labial furrows either absent, or extending around corner of mouth 



if present. 



23. Scyllium edtuardsii Voigt (in Cuvier, Tierreich, s, 1832: 504), S. Afr.; S. marmoratum Bennett (Mem. Raffles, 

 1830: 693), Malaysia, India; and A telomycterus macleayi Whitley (Aust. Zool., 9, 1939: 230), Australia. 



24. Mem. Harv. Mus. comp. Zool., $6, 1913: 100, 101. 



