340 THE PLAGIOSTOMIA. 



Raia scabrata, sp, nov. 

 Plate 21; Plate 44, fig. 1-3. 



Raia radiata Storbr, 1839, Report fishes, p. 201; Gill, 1861, Proc. Acad. nat. sci. Phil., p. 61 extra; 



Garman, 1874, Proc. Bost. see. nat. hist., 17, p. 178; Jordan & Gilbert, 1882, Bull. 16, U. S. nat. 



mus., p. 41; Goode & Bean, 1896, Mem. M. C. Z., 22, p. 25, pi. 9, f. 27 juv.; Jord. & Everm., 



1896, Bull. 47, U. S. nat. mus., p. 69. 

 Raia laeris Storer, 1867, Mass. fishes, p. 266, pi. 39, f . 2. 



Closely allied to R. radiata but larger, less rough, and rather more angular. 

 The small scales are sparsely scattered or absent from considerable areas; both 

 scales and tubercles are stellate-based. Large tubercles occur in the median 

 dorsal series, in a pair on each shoulder, hinder larger, as a single tubercle in 

 front of and one behind each eye and one behind each spiracle, and in three 

 rows of smaller ones above the snout. A row of much smaller tubercles at each 

 side of the median extends from the shoulder girdle backward and is more or 

 less doubled or irregular on the tail. A few small scales above the ventrals. 

 On the pectorals the bucklers are large near the bases of the fins and decrease in 

 size toward the margins near which they disappear. Most often the second 

 dorsal is separated from the first by a space with a tubercle. Males of 26 inches 

 in length are nearly mature; they have two rows of erectile tenacula near the 

 outer angles on the pectoral fins. 



Comparative smoothness of the skin between the tubercles, greater size, 

 and slight differences in dentition distinguishes this form from the European 

 R. radiata. The difference in regard to squamation appears to be quite as 

 marked on the young as on adults. 



Back brown, somewhat clouded, spotted with darker brown on young; 

 lower surfaces white. Specimen No. 254, M. C. Z., 23 inches in length is milk- 

 white with a few spots of reddish brown on the middle of the back, with a brown 

 spot larger than the eye across each dorsal, and with three blotches of brown 

 across the base of the tail. Rarely a specimen is blotched with brown on the 

 ventral surface. 



Specimens described from Massachusetts Bay. Total length 31 1, from 

 snout to abdominal pores 16, and greatest width 23 inches; younger individual, 

 length 14i, greatest width 8i inches. 



