19 FISHES OF SINALOA. 3901 
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 grey or white spots, half 
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 red- 
dish of the belly conspicuous. 
One specimen, 12 inches long. Type No. 1587, L.S. 
Je Univ. Mus: 
20. Aitobatus narinari (Euphrasen). GaAviLan. 
Rather common in the harbor of Mazatlan, where it 
was also taken by Gilbert; a beautifully colored species 
reaching a large size. 
Length of disk 1% in width; proximal half of anterior 
margin of pectoral fins straight, distal half convex; pos- 
terior margin concave, the end of each ray forming a ° 
small scallop; lateral angle sharp. 
Snout forming an angle, from its tip to division of nasal- 
lobes, 1% times breadth of head; width of snout 14 times 
distance from its tip to the division of nasal-lobes; nasal- 
lobes projecting back over the mouth; width of mouth 
1% its distance to tip of snout; numerous blunt buccal 
papilla around upper dental plate and on ridge between 
nostrils; interorbital 434 in disk; eyes smaller than spir- 
acles, which are as long as base of dorsal. Ventrals well 
rounded, 3% in length of disk; tail 3% times disk. First 
caudal spine equals base of dorsal, which is half second 
spine. 
