On a new Ceratopterine Kagle-Ray. 227 
XXIII.— Description of a new Ceratopterine Eagle-Ray from 
Jamaica. By G. A. BouLENGER, F.R.S. 
AmoneG some Fishes brought home from Jamaica by the 
Rey. J. Seed Roberts, who for many years has been paying 
special attention to the fish fauna of that colony, there was a 
Ceratopterine Ray which neither Mr. Roberts nor myself 
succeeded in identifying. It has much in common with 
Bancroft’s Cephalopterus hypostomus, described from Jamaica 
in 1830, but is at once distinguished by the absence of teeth 
in the lower jaw, which precludes our referring it to the 
genus Dicerobatis, in which teeth are present in both jaws. 
The allied genus Ceratoptera agrees in this, that teeth are 
developed in one of the jaws only, but it is the lower instead 
of the upper that bears them; and, besides, the position of 
the mouth and the shape of the pectoral fin are entirely 
different. I therefore find myself compelled to propose a 
new genus for the reception of the Ray, with which I wish to 
associate the name of its discoverer. 
CERATOBATIS, gen. nov. 
Like Dicerobatis, Blainv., but teeth restricted to the upper 
jaw. 
Ceratobatis Robertsi7, sp. n. 
The band of teeth occupying only half the width of the 
mouth, its width 10 times in its length; teeth tessellated, 
hexagonal, 2 to 3 times as broad as long, rugose with nume- 
rous obtuse ridges. Mouth inferior, wide. Pupil vertically 
elliptic. Body smooth; pectoral fins with nearly straight, 
slightly convex anterior and slightly concave posterior border. 
Cepbalic fins measuring a little less than the width of the 
mouth ; spiracles behind the eyes. The space between the 
last branchial clefts one fourth that between the first. 
Dorsal fin between the ventrals. Tail slender, without spine, 
nearly twice as long as the body. 
millim 
Length of disk, without cephalic appendages........ 350 
Bivclbly of disks Ve tes ein ceniciee f ccriae ele wistele clsvs sie «oe 780 
Sea eM MTAT ifaes crc fod Pe a siclore ngs) a¥as sieravw oip'0.0 obs wre» dyaiess 10) 
PRUE GUAGE ia enor p: east lini nye cals sheyss veagel ajsheie's 105 
PATS UCT OCW Laat «win nin jolei Sys) sislarela\« v1] ¢/el shnhe) =) s\oln) e's 12 
RUCHITH RETNR cPetcdaya anes cisfotsrcis die, niesnsiave cenploneists eisreferaruioe 70 
Tail @eeoeceeeeserrerereereerevenerreore @eoerserereververs 620 
