RAIA PLUTONIA. 335 



(2) Total length 27, snout to mouth 7, snout to pores 17, and greatest 

 width 17 inches. 



The northern variety, R. nidrosiensis, is darker in color and less spotted. 

 Europe; Mediterranean. 



Raia maroccana. 



Raia maroccana Schneider, 1801, Bloch Ichth., p. 367; Muller & Henle, 1841, Plagios., p. 150, pi. 

 49, f. 2; DuMERiL, 1865, Elasm., p. 559; Gunth., 1870, Cat., fishes Brit, mus., 8, p. 466. 



Disk rhomboid, snout long, three and one half times the interorbital width, 

 pointed, anterior margins undulated, httle indented, outer angle about 90°, 

 hinder margins and angles rounded. Teeth of adult male conical, pointed, in 

 41 series on the upper jaw. Skin naked, excepting a few minute spines on the 

 middle of the back, on the margins of the disk and under the snout, on the head, 

 also a group of larger ones on the forward ends of the pectorals, and the tubercles 

 in a row on the orbital ridges and in two lateral rows and a median row, of 

 alternating sizes, on the tail. Tail longer than the body moderately slender; 

 dorsal fins separated by a space. Male with tenacula. 



Total length of an adult male about 22, length of disk 11, and greatest 

 width 13^ inches. 



Light brow^nish, nearly uniform. 



Morocco. 



Eastern North American species. 



Rata plutonia. 

 Plate 18, fig. 1. 



Rnia plutonia Garman, 1881, Bull. M. C. Z., 8, p. 236; Jordan & Gilbert, 1882, Bull. 16, U. S. nat. 

 mus., p. 878; Goode & Bean, 1883, Bull. M. C. Z., 10, p. 225; Gijnther, 1887, Challenger rept. 

 Zool., 22, p. 10; JoRD. & Everm., 1896, Bull. 47, U. S. nat. mus., p. 69; Goode & Bean, 1896, 

 Mem. M. C. Z., 22, p. 27, pi. 8, f. 26. 



Disk rounded, anterior margins slightly concave near the middle; snout, 

 outer angles and hinder angles, and margins broadly rounded, tip of snout a 

 blunt angle. Rostral cartilage short. Mouth little curved, width about half 

 the distance from the end of the snout. Teeth in about 32 rows (juv.). Eyes 

 large, orbits longer than their distance apart. Anterior nasal valves reaching 

 the mouth, narrow, joined to a wide isthmus; posterior valves short, tubular. 

 Ventral fins deeply notched, anterior portion narrow, longer than the posterior. 

 Back and tail covered with small closely set hooked spines. The larger tubercles 



