2754 Bulletin 4.7, United States National Museum. 



like, with a scarcely perceptible fold of skin on its dorsal side. Ground 

 color olive brown, everywhere with small dark points, not so close set as 

 in Pteroplatea rava, indistinct grayish spots, ^ as large as iris, scattered 

 over the body among the dark points, these spots more distinct on 

 anterior edge of disk; tail mottled with darker; lower parts light. 

 Markings nowhere so distinct as in P. rava. Very common on sandy 

 shores everywhere about Mazatlan, from which locality it was originally 

 described ; also taken by Dr. Gilbert. 



Page 87. After Pteroplatea marmorata add: 



130(a). PTEROPLATEA RAVA, Jordan & Starks. 



(MANTARAIA COLORADA.) 



Length of disk 1$- width; snout forming an angle which is almost a 

 right angle; pectorals slightly concave medially; posterior margin of 

 disk weakly convex; posterior angle not broadly rounded, but curved in 

 somewhat suddenly ; lateral angles acute. A line drawn through lateral 

 angles would bisect a line from snout to tip of tail. Interorbital 1 in 

 snout; eye 1 in spiracles; mouth 7 in disk, 1 in snout; tail straight 

 and slender, with a very slight fold on dorsal side. Ground color light 

 olive brown, thickly set with sharp-cut black points; conspicuous gray 

 or white spots, | as large as iris, scattered over the body, around which 

 the black spots form rings ; brighter yellowish spots and half-spots around 

 anterior edge of disk ; tail mottled above with darker : lower parts chiefly 

 light orange red or rust-colored in life. All the markings are very distinct 

 and clear cut, the reddish of the belly conspicuous. Mazatlan. One speci- 

 men 12 inches long, (ravus, reddish.) 



Pteroplatea rava, JORDAN &. STARKS, Fishes of Sinaloa, 390, 1895, Mazatlan, Mexico. 

 (Type, No. 1587, L. S. Jr. Univ. Mus. Coll. Hopkins Exped. to Sinaloa.) 



Page 90. After Myliobatis californicus add : 



134(a). MYLIOBATIS ASPERRIMUS, Gilbert, new species. 



4 



Upper surface of head and body, excepting the snout, an area on outer 

 side of spiracle, the pectoral margin and its posterior angle, and the ven- 

 tral fins thickly covered with minute, usually stellate prickles, of uniform 

 size, most numerous on median portions of head and back ; those on basal 

 ^ or $- of pectoral least crowded and arranged in definite longitudinal 

 series, corresponding with the muscle bands; tail very rough throughout, 

 covered with similar stellate prickles and also crossed by numerous narrow 

 grooves, or indented lines, mostly convex forward, somewhat irregular in 

 position and direction, and not corresponding on the two sides. In the 

 type they follow at an average interval of about 10 mm. Lower side of 

 disk mostly smooth, with some prickles on the basal part of pectorals 

 anteriorly, arranged in lengthwise series, and other patches on lower side 

 of head, belly, and base of ventrals. Color dusky brown above, the 

 anterior portion of pectorals with 8 to 10 narrow transverse bars of bluish 



