6 FISHES FROM BRAZIL 



also a few small round, light spots scattered sparsely over the middle of 

 the back. The dark spots are somewhat larger and more conspicuous on 

 the tail and run back on the caudal fin. On one specimen there are two 

 pairs of dark spots on the rostral ridges. The under part of the snout has 

 a black blotch. 



Family PRISTID^. 



5. Pristis perrotteti Valenciennes. 



A large "saw," 4 feet in length, was obtained in Natal. It has 18 

 teeth on each side and is much more tapering than in Pristis pectinatus. 



6. Pristis pectinatus Latham. 



One small specimen was taken at Natal, 



Family DASYATID^. 

 7. Dasyatis gymnura (Miiller). 

 A specimen taken at Para. 



8. Dasyatis say (Le Sueur). 



Two specimens with the disk 1 1 inches in length, caught in a trawl in 

 deep water at Natal, are referred to this species, though there are some dis- 

 crepancies between them and current descriptions. The disk is no longer than 

 broad, and is nowhere concave. The front of the disk is nearly straight on 

 each side, meeting at an angle at the snout. The greatest width is opposite 

 the gill openings. The caudal is no longer than the disk, and has a broad 

 fold above and below. There are 6 or 7 tubercles on the median line of 

 the back in front of the shoulder girdle, and one some distance behind this, 

 in one of the specimens. A group of 2 or 3 very small spines is on the 

 shoulder. The skin is otherwise perfectly smooth. 



The color in one of them in life was light dusky green, growing red- 

 dish toward the edges of the disk. Posteriorly it was bordered with dusky 

 and narrowly edged with white. The caudal was white, with the dorsal 

 and ventral folds black. The other specimen is very much darker in alcohol, 

 but the posterior white border of the disk is evident. Both of the specimens 

 have large irregular black blotches below. 



9. Potamotrygon hystrix (Miiller and Henle). 



The species of this genus are very much in need of revision. Doctor 

 Eigenmann has included this and the next with several others under one 



