418 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



Skin soft above, with small asperities upon snout, interocular and 

 crown, larger and very rough on back medially posteriorly and base 

 of tail, upon middle of back form 3 or 4 longitudinal series of large 

 convex scutes. 



Tail nearly 2^ times disk, strongly depressed basally ; single spine 

 inserted little before first third in tail ; lower fold extends from first 

 fourth of tail nearly % total tail length; pectorals partly rhom- 

 boidal, front lateral edges partly convex, outer angles rounded, hind 

 edges partly rectilinear ; ventrals with outer angles rounded. 



Gray-brown above, darker medially, below tail and especially ter- 

 minally. Lower fold of tail brown passing to black at its free border. 

 Below disk and tail whitish. Length, 1,000 mm. (Chabanaud.) 



Gulf of Siam. Said to be related to Dasyatis sephen in body more 

 convex, pectorals short before snout, and 4 oral papillae instead of 5. 



DASYATIS AGULHENSIS Barnard 



Dasydatis agulhensis Baknard, Ann. South African Mus., vol. 21, pt. 1, p. 78, 

 1925 (type locality: Agulhas Bank, South Africa). 



Snout obtusely angular, with small median point ; eyes small, closer 

 together than spiracles; teeth in about 46 rows, not angularly bent, 

 each tooth more or less hollowed in center ; cutaneous flaps on mouth 

 floor 9, 3 median, 1 submedian, and 2 lateral; outer angles of inter- 

 nasal flap quadrate. 



Disk smooth, except 3 or 4 small tubercles on radiate bases on point 

 of snout, 1 or 2 slightly larger ones before each orbit and 4 com- 

 pressed spinelike scutes in middle of back between posterior gills. 

 Tail tuberculate. 



Tail ly^ times body length, not basally depressed, with lower cu- 

 taneous fold extending from beneath spine to or almost to tip, about 

 % tail depth; single caudal spine length i/^ its distance from tail 

 base; pectorals form disk little wider than long, front margin of 

 pectoral slightly longer than hind margin also straight or slightly 

 concave, lateral and posterior angles rounded. 



Uniform bluish slate. Length, 1,905 mm. (Barnard.) 



South Africa. 



DASYATIS SCHREINERI (Gilchrist) 



Trygon schremeri Gilchrist, Trans. Roy. Soc. South Africa, vol. 3, p. 33 (text 



fig.), 1913 (type locality: "Off the rocks at St. James in False Bay"). 

 Dasytatus schreineri VonBonde and Swart, Marine Biol. Surv. South Africa 



Rep., pt. 3, 1922, p. 16, 1924 (reference). 

 Dasyatis schreineri Barnard, Ann. South African Mus., vol. 21, pt. 1, p. 76, 1925 



(False Bay, Agulhas Bank to 40 fathoms). — Fowler, Proc. Acad. Nat. Sci. 



Philadelphia, vol. 86, p. 409, 1934 (Natal). 



Eyes small; teeth with transverse ridges, in about 33 to 48 rows; 

 5 oral papillae on mouth floor; outer angles of intemasal flap 

 rounded ; interorbital less than interspirncle width. 



