304 THE PLAGIOSTOMIA. 



protractile; teeth bands rather wide, resembling those of Narcacion rather than 

 those of Narcine; teeth small, numerous, tricuspid. Eyes small. Spiracles 

 large, close behind the eyes, fringed. Gill openings small. A large electric 

 organ between the head and each pectoral. Dorsals small, above the ventrals. 

 Vent far behind the middle of the total length. 



Hypnarce subnigrum. 



Hypnos subnigrum Dumeril, 1852, Rev. & mag. zool., p. 279, pi. 12; 1865, Elasm., p. 520; Gunth., 



1870, Cat. fishes Brit, mus., 8, p. 453. 

 Hypnarce subnigrum Waite, 1899, Mem. Austr. mus., 4, p. 42; 1902, Rec. Austr. mus., 4, p. 180. 



Disk longer than wide, broader forward, rostral region short. Mouth and 

 eyes in the anterior sixth of the length. Spiracles larger than the eyes, borders 

 fringed. Mouth and bands of teeth of moderate width; teeth small, narrow, 

 with three slender, acute cusps. Ventrals elongate, broad, rounded, united 

 below the tail. Dorsals subequal, close together above the hinder half of the 

 ventrals. Tail less than a fourth of the total length. Skin naked, smooth. 



Waite mentions a specimen of two feet three inches in length. 



Young blackish brown; large specimens taken by Waite were of a rich 

 yellowish brown color. 



Sydney, New South Wales; West Australia. 



Narcacion. 



Narcacion Klein, 1742, Hist, pise, mis3., 3; 1777, Neuer schaupl., 4, p. 726; Walbaum, 1792, Artedi, 



p. 580; Gill, 1862, Ann. N. Y. lye., 7, p. 387. 

 Torpedo Houttoyn, 1764, Nat. hist., 6, p. 453; Dumeril, 1806, Zool. anal., p. 102. 

 Tetronarce Gill, 1861, Ann. N. Y. lye., 7, p. 387. 

 Gymnotorpedo Fritsch, 1S86, Arch, physiol., p. 365. 

 Finibriotorpedo Fritsch, 1886, Arch, physiol., p. 365. 



Disk wider than long, subcircular; snout short, weak, flexible; tail distinct, 

 short, with two dorsals, a well-developed caudal fin, and a low keel on each side. 

 Ventrals not united, anteriorly below the pectorals. Mouth crescentic, with a 

 longitudinal fold at each angle. Nostrils small; anterior valves united, forming 

 a broad flap in front of the mouth, free behind and at the sides. Teeth small, 

 in pavement; broad-based, crown with an acute angle directed inward. Spira- 

 cles moderate, at a short distance behind the eyes, with or without fringes on the 

 margins. Rostral cartilage weak, short, reduced to a pair of slender rods. 



Tropical and temperate seas. 



