50 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



sting rays ; inliabiting warm seas. Similar in habits to the Trygonidce. 



(Groui> Mylioiatina Giiuther, viii, 488-495.) 



* Muzzle entire. 



a. Teetli in a single series, very broad Aetobatis, 41. 



aa. Teeth in several series, the middle series very broad Myliobatis, 42. 



** Muzzle emargiuate ; cephalic fins below the level of the disk ; teeth in several 

 series Rhinoptera, 43. 



41.— AETOBATIS Muller & Heule. 



Bishop Bays. 



(Blainville; Miiller & Henle, Plagiostomen, 1837: type Raja narinari Euphrasen.) 



General form of Myliobatis. Muzzle entire. Teeth flat, broad, form- 

 ing a single series corresponding to the middle series in Myliobatis, there 

 being no small lateral teeth. Upper dental lamina straight, lower 

 curved, the latter projecting beyond the upper. Free border of the 

 nasal valve deeply emarginate. Skin smooth. Tropical seas, (aird-:, 

 eagle; (Sazcc, ray. 



66. A. aaariBiari (Euphrasen) Muller & Henle. 



Bisk twice as broad as long, its anterior borders a little convex, pos- 

 terior concave, outer angles pointed. Cephalic fin about one-third 

 broader than long. Teeth of the lower jaw straight or more or less 

 angularly bent. Tail 3 or 4 times length of disk. Brown, with small 

 round pale spots. {Dumeril.) Virginia to the Indian Ocean ; not very 

 common on our coast. 



{Raia narinari Euphrasen, Vet. Ak. Nya. Handl. 1790, xi, 217: Raia flagellum 

 Bloch, Schn. 301; Giinther, viii, 492; Dumeril Hist. Nat. Poiss. i, 642.) 



42.— MYLIOBATIS C. Dura6ril. 



Eagle Rays. 



(Dumeril in Cuvier Regne Animal, ii, ed. 1, 137, 1817 : tyi)e Raia aquila Linmcus.) 



Disk broad, the outer angles acute ; cephalic flus forming a soft con- 

 vex appendage in front of the snout ; jaws about equal ; median teeth 

 very broad, much broader than long in the adult, proportionally nar- 

 rower in the young ; several series of narrower teeth on each side of 

 the median series. Free edge of the nasal valve not deeply emarginate. 

 Tail very long and slender, with a small dorsal fin and one or more ser- 

 rated spines. Skin smooth or nearly so. Size large. In all warm seas. 

 {{jLuXia-, a grinder; Buti<;, raj'.) 



