RAIA DIAPHANES. 339 



Agassiz off the New England Coast. Total length 22^, tail from axil of ventrals 

 111, disk to ends of pectorals II5, greatest width 14 inches. 



Rusty brown, clouded with darker, apparently unifo.-m. Originally 

 described from an immature female, with a white spot on the middle of the back 

 and another across the base of the tail. Other differences occur in the types 

 but they are such as may be peculiar to the young. 



RaIA DIAPHANES. 

 Plate 22, fig. 1. 



liaia ocellata Mitch., 1815, N. Y. lit. & philos. trans., 1, p. 477; Storer, 1839, Report fishes, p. 191; 



DuMERiL, 1865, Elasm., p. 539; Garman, 1874, Proc. Bost. soc. nat. hist., 17, p. 177; 1888, Bull. 



M. C. Z., 6, p. 91, pi. 30; Jordan & Gilbert, 1882, Bull. 16, U. S. nat. mus., p. 40; Jord & Everm., 



1896, Bull. 47, U. S. nat. mus., p. 68, pi. 10, f. 30 (non R. ocellata Russell, 1803). 

 Raia diaphanes Mitch., 1815, N. Y. lit. & philos. trans., 1, p. 478; DeKay, 1842, N. Y. fish., p. 360, 



pi. 67, f. 218; Storer, 1867, Mass. fishes, p. 264, pi. 39, f. 1. 

 Raia batis Wyman, 1864, Mem. Amer. acad., new ser., 9, p. 34; Ann. mag. nat. hist., ser. 3, 14, p. 399. 



Anterior margins of disk waved, prominently convex opposite the eyes, 

 concave near the middle, outer and hinder angles and margins rounded. Snout 

 short, blunt, little longer than the interspiracular width. Mouth waved; 

 teeth in about 90 rows (80 to 110). Back rough with sharp spines on the head, 

 around the eyes, along the anterior margins and on the front ends of the pec- 

 torals, and in places about the shoulder girdle near the hind margins of the 

 pectorals and above the ventrals. Tail rough. The tubercles are absent from 

 the median line of the tail and to some extent from the middle of the back; a 

 lateral series begins above the abdomen on each side, and is continued on the 

 tail with one or more additional rows. Males with a band of erectile tenacula 

 near the outer angles of the disk; claspers elongate, more slender and narrow 

 backward. Dorsal fins near the end of the tail usually not separated by tubercles. 

 Females are more spinose than males. 



Brown with small spots of darker and with or without ocellate spots of 

 white on the pectorals opposite the abdomen ; below white. 



One of the most common species off the eastern United States. 



Distinguished from its nearest ally, the small species R. erinacea, by the 

 dentition and by colors. 



