82 Bulletin 47, United States National Museum. 



in disk; eyes small, much less than spiracles. Mouth 2+ in its distance 

 from snout. Caudal spine very large, a little more than twice interorbital 

 width, its insertion in front of middle of tail. Skin entirely smootli, except 

 for a series of a few (2 to 8) strong, broad-rooted spines or bucklers on 

 upper part of tail before caudal spine; these are straight, sharp, directed 

 backward, their height equal to width at base, which is greater than pupil. 

 Color plain brown. L. 18 inches. Panama. (ac77r<r, shield; oipd, tail.) 

 UroJop/ms a.s;'id«.-Hs, Jordan & Gilbert, Bull. U. S. Fish Com., 1881, 307, Panama. (Type, Nob. 

 29410; 29307 ; 29454.) 



120. rKOLOPHUS ASTERIAS, Jordan & Gilbert. 



Disk almost round, a little broader than long, about as long as tail; an- 

 terior margins of disk nearly straight, the tip acute, slightly exserted. 

 Snout, from eye, 4 in disk. Eyes small, much smaller than spiracles, about 

 \ interorbital width. Mouth 2\ in distance to tip of snout. Teeth 

 sharp in males, pavement-like in females. Caudal spine very long, longer 

 than snout, inserted in front of middle of tail. Skin above everywhere 

 covered with small stellate prickles, these larger and more numerous on 

 median line; ventrals smooth; both sexes equally rough; median line of 

 back with a series of 18 to 32 sharp, recurved, spinules, from shoulders to 

 caudal spine, these becoming larger and sharper backward, but all much 

 smaller than the prickles in V. (tspidurits. Color plain light brown. 

 Mazatlan to Panama, not rare, (atrrz/p, a star, from the stellate spines.) 



Urohphns usierias, Jordan & Gilbert, Proc- U. S. Nat. Mus., 1882, 579, Mazatlan; Panama. 

 (Type, Nos. 28204 ; 29524 ; 29542 ; 29058 ; 29318.) 



S3. DASYATIS, Rafinesque. 

 (Sting Rays.) 



Dasybatus, Klein, 1742, (pre-Linnsean). 



Dasyatis, Rafinesque, Caratteri di Alcuni Nuovi Gen., 16,1810, (itjits=:pastinaca). 



Vroxis, Rafinesque, Indico d'lttiol. Sicil., Gl, 1810, (ly'its). 



Trigonobatns, Blainville, Jour. Phys., 181G, 261, {vuluaris). 



Ti-ygon, (Adanson), Cuvier, Regoe Animal, Ed. i,130, 1817, (pastinaca). 



Hemitrygon, Muller & Henle, Mag. Nat. Hist., 1837, 90, {henuelli). 



IlimaHtura, MiiLLER & Henle, Wiegtnann's Archiv., 1837, 400, (uamak), 



Pastinaca, SwAiNSON, Classu. Anim., 319, 1839, (olivacea). 



Anacanlhus, Ehrenberg, in Swainson, I. c, (orbiCHlaris). 



Pastinaca, 1)E Kay, N. Y. Fauna: Fishes, 373, 1842, ( paslinaca). 



Z)(Mi(<a/is, Garman, in Jordan & Gilbert, Synopsis, 05, 1883, {paslinaca; corrected orthography). 



Disk oval, flat, with rounded angles. Tail very long and slender, whip- 

 like, without fin, but often with 1 or 2 vertical membranous folds; a strong 

 serrated spine toward the base of the tail. Skin more or less spinous or 

 prickly, rarely smooth. Teeth small, paved; a few papillaj usually pre- 

 sent in the mouth behind the lower jaw. Species about 30. Sting rays 

 of large size, abundant in warm seas. Many of the spinous species are 

 nearly or quite smooth when young, becoming rough with age. Some of 

 our species are yet imperfectly known and much of the synonymy is 

 uncertain. ((5aaif, shaggy or rough; iiarl^, a skate; abbreviated from 

 DasyhaUs. ) 



