392 CALIFORNIA ACADEMY OF SCIENCES. 



Color bluish black with many round yellowish spots 

 scattered equally over the back and ventral fins; spots about 

 as large as eye on back, smaller on head, sometimes two 

 spots run together forming an elliptical spot, about sixteen 

 spots from eye along anterior margin of pectoral to lateral 

 angle; posterior margin of pectoral very narrowly mar- 

 gined with white; ventral side pearly white. 



From the description of A^tobatus laticefs this species 

 differs in the following respects : disk not so broad ; tail 

 not so long; width of head and snout less; ventrals not 

 truncated behind; pectorals not margined with blackish; 

 spots on ventrals not assuming the form of ocelli. 



Five large specimens obtained; length of disk in each, 

 15 inches. 



This description has been compared by Dr. Barton W. 

 Evermann, with specimens of yStohatits narinari from 

 Brazil. No difference of any importance appears, and 

 in his judgment the Atlantic and Pacific Coast American 

 forms are identical. 



Note. — This species has been several times obtained 

 by Dr. Gilbert and others in the Gulf of California, hav- 

 ing been identified as ^tohatiis laticeps of Gill. It does 

 not, however, agree with Dr. Gill's description and there 

 is no evidence that his specimen came from Mexico, ^to- 

 hatus laticeps was described from an example from un- 

 known locality received from San Francisco. It is there- 

 fore quite as likely to have come from Honolulu or from 

 China, as from the Gulf of California. 



The following is Dr. Gill's description: 



'•'■Aetobatis laitceps Gill. 



" The greatest width is rather 7]tore than twice as great 

 as distance from snout to front of anus. The head is 

 broad and nearly equals the distance from snout to divis- 

 ion of nasal lobes. The snout is obtusely angulated in 

 front, and at its sides is convex and scarcely angulated; 



