Jordan and Evermann. Fishes of North America. 2755 



white, most of which break up into series of spots toward outer margin 

 of disk, the posterior ones also breaking up toward middle line ; the bars 

 and spots fainter anteriorly, becoming whiter and more intense posteriorly ; 

 toward outer angles of disk the bars sometimes separated by intermediate 

 series of light round spots, the bars usually failing to meet across the 

 back ; posterior portion of disk including base of tail and upper surface 

 of ventrals covered with round white spots not much larger than pupil, 

 some of those immediately succeeding the bars showing a transverse serial 

 arrangement; top of head with one or more pairs of indistinct light spots; 

 margin of snout and of pectorals blackish ; spiracular border black ; dor- 

 sal with a black blotch posteriorly ; underside of head and disk bright 

 white ; proximal portion of tail blackish above, lighter below, the entire 

 tail becoming black more posteriorly. 



Dimensions of type specimen. 



Millimeters. 



Length of disk to front of anus 272 



Length of disk to posterior edge of pectorals 338 



Width of disk 345 



Length of tail (not perfect) 1,215 



Greater width of head at origin of pectorals 79 



Width of cranium between orbits 45 



Width of snout opposite front of eye 55 



Tip of snout to middle of nasal flap 60 



Length of nasal flap 26 



Greatest width of nasal flap 35 



Diameter of iris 10 J 



Width of mouth 33 



Distance between anterior gill openings 75 



Distance bet\veen posterior gill openings : 45 



Distance from anterior to posterior gill openings TTI 45 



Length of spiracle 26 



Length of fontanelle 60 



Greatest width of fontanelle (at anterior end) 23 



Rostrofrontal fontanel scarcely constricted anteriorly, the bounding 

 ridges diverging abruptly at their anterior ends. Nasal flap with a shal- 

 low median notch, covering the mouth except the median portion of lower 

 dental plate; posterior margin coarsely fringed. Teeth in each jaw in 1 

 broad median row, and 3 lateral rows, those of median row about 5 times 

 as broad as long anteroposteriorly. 



One specimen, a male, with undeveloped claspers which do not nearly 

 reach edge of ventrals, from Panama. (Gilbert. ) (asperrimm, very rough. ) 



Myliobatis asperrimus, GILBERT, Fishes of Panama, MS. 1898. (Type, No. 11895, L. S. Jr. 

 Univ. Mus. Coll. Dr. Gilbert.) 



134(b). MYLIOBATIS GOODEI, Garman. 



Disk about f as long as broad ; lateral angles acute, bluntly rounded at the 

 apices ; posterior angles of pectorals nearly right ; snout very broad, short, 

 with a slight prominence in front; the fin, or flange, beneath the eye at 

 the side of the head is very wide, much wider than in either M.freminmllei 

 or M. californicus; eye very small, without a prominence above in either 



