388 CALIFORNIA ACADEMY OF SCIENCES. 



a third procured by Mr. James A. Richardson in the 

 harbor of La Paz. Specimens had also been obtained by 

 Dr. Gilbert, at Panama, in 1883, but having been de- 

 stroyed by fire, the species has remained undescribed 

 until the present time. 



Snout 3^ in length of disk; preocular part of snout 

 equals preoral; interocular space in snout, 1% ', width of 

 mouth, 2^. Eye much smaller than spiracle; spiracles 

 edged with small tubercles. Length of disk equal to its 

 width; disk equal to length of tail, without caudal fin; 

 tail with a loose fold of skin on each side. First and 

 second dorsals equal, rounded behind; ventrals large, 

 ending midway between posterior edge of disk and caudal 

 fin. Color: Pale olive brown, a little clouded with 

 darker; second dorsal edged with pale; dots on head 

 dusky. . 



Length of largest specimen, 20 inches. Type, No. 

 1699, L. S. Jr. Univ. Mus. 



The Spanish name Entemedor seems to be equivalent 

 to Intimidatoi- . 



Family DASYATIDyE. 



14. Urolophus asterias Jordan & Gilbert. Raia. 

 Very common in the surf and on the sandy beaches 



about Mazatlan. Spinules on back and tail 18 to 32 in 

 number. The upper side of the disk is marked with 

 round dusky spots, faint, as if washed or faded out. 



15. Urolophus rogersi Jordan & Starks, n. sp. 



Disk broader than long by a distance 2>^ times the 

 interorbital width ; anterior margins of disk nearly straight, 

 the tip of snout projecting; snout from eye, 3^ in length 

 of disk; eyes little smaller than spiracles; width of mouth, 

 2^ times in preoral part of snout; caudal spine inserted 

 in front of middle of tail. Skin with minute prickles on 



