100 



THE PLAGIOSTOMIA. 



length of the snout. Spiracle separated from the orbit by nearly one third 

 of the orbital length. Gill openings moderate, hindmost two above the base of 

 the pectoral. Fleshy portions of the pectorals closely bound up with the 

 muscles of the body, angles of fins rounded, hind margins nearly straight. Base 

 of first dorsal extending little backward of the bases of the ventrals. Second 

 dorsal the longer, base reaching little behind the base of the anal. Anal base 

 very long, two and one half times the length of the base of the first dorsal. Cau- 

 dal three elevenths of the total length. Scales minute, three cusped. Caudal 

 without modified scales on its upper edge. 



Uniform warm brown; snout and margins of fins blackish. 



Original description from a twenty inch female containing two eggs, the 

 cases of which were peculiarly constricted toward each end. 



Off the western coasts of North America. 



Atelomycterus, gen. nov. 



Form somewhat like that of Chiloscyllium, elongate, slender, body cavity 

 short, tail longer. Eye large, orbit long; lower lid well differentiated, upper 

 edge closing inside of the upper lid, with a fold and apparently translucent or 

 semitransparent. Spiracle small, close to the eye. Nostrils nearly midway 

 from the mouth to the end of the snout, with a rudimentary nasoral groove, 

 without cirri, without posterior nasal valves; anterior valves reaching the 

 mouth in rounded lobes, separated by a median attachment in front of the 

 symphysis of the jaws. Mouth with long labial folds and strong jaws. Teeth 

 small, three cusped, median cusp longest. Gill openings moderate, hindmost 

 above the pectorals. Pectorals small, rounded. Dorsals larger than the anal, 

 origin of first dorsal above the ventrals; hind angles of dorsals and anal pro- 

 duced. Subcaudal narrow, without a prominent lobe. 



India to the Archipelago. 



Atelomycterus marmoratus. 



Scyllium marmoratum Bennett, 1830, Mem. Raffles, p. 693. 



Scylliwn ■maculatum Gray & Hardwicke, 1832, 111. Ind. zool., 1, pi. 98, f. 1; Muller & Henle, 1841, 

 Plagios., p. 5, pi. 7; Richardson, 1846, Rept. Brit, assoc. adv. sci. for 1845, p. 193; T. Cantor, 

 1849, Malay, fishes, p. 1373; Bleeker, 1852, Verb. Bat. gen., 24, Plagios., p. 16; Dum£ril, 1865, 

 Elasm., p. 319; GtJNTH., 1870, Cat. fishes Brit, mus., 8, p. 400. 



Scyliorhinus marmoratus Regan, 1908, Ann. & mag. nat. hist., ser. 8, 1, p. 462. 



Body slender forward, resembling that of Chiloscyllium rather than that of 

 Scyliorhinus, less than half of the total length. Head nearly one sixth of the 



