MYLIOBATIS CALIFORNICUS. 429 



flange at side of head narrow- 

 pectoral tips narrow, rounded 



dorsal origin more than 2 lengths of base behind ventral bases 



aquila (page 431) 

 Snout elongate, pointed 



flanges moderately wide 



pectoral tips narrow, pointed 



dorsal origin Is lengths of the base behind bases of ventrals 



freminvillii (page 432) 

 flanges narrow 



pectoral tips moderate, rounded 



dorsal origin I2 lengths of base behind ventral bases 



tobijei (page 433) 

 Snout short, broad, rounded 

 flanges (?) rather narrow 



pectoral tips narrow, pointed 



dorsal origin near 1 length of the base behind bases of ventrals 



spotted or barred with blue or white tenuicaudafus (page 433) 



MYLIOBATIS CALIFORNICUS. 

 Plate 49, fig. 4-6. 



Rhinoptera vespertilio Girakd, 1856, Proc. Acad. nat. sci. Phil., p. 137; 1857, Journ. Bost. soc. nat. hist., 6, 



p. 544, pi. 26. 

 Holorhinus vespertilio Gill, 1S62, Proc. Acad. nat. sci. Phil., p. 331. 

 Myliobatis californicus Gill, 1865, Ann. N. Y. lye, 8, p. 137; Jordan & Gilbert, 1882, Bull. 16, U. S. 



nat. mus., p. 51; Jord. & Everm., 1896, Bull. 47, U. S. nat. raus., p. 89. 



Width of disk less than twice the length of the body or a little more than 

 half of the total length in a specimen of twenty-two inches. Each pectoral 

 nearly as long as broad, not falciform, broadly rounded at the outer extremity, 

 nearly straight on the anterior margin, slightly convex on the posterior, acute 

 in the hinder angle and convex on the inner free margin. Rostral fins broad 

 across the end of the snout, moderately wide at the side of the head, where 

 joining the pectorals. Skull broader than long; fontanel broad in front, broad 

 and rounded posteriorly. Median teeth three to five times as wide as long, 

 Plate 49, fig. 4-6. Anterior nasal valves confluent in a broad flap, free behind, 

 with rounded angles and a narrow fringe at the mouth. Ventrals broader than 

 long, subtruncate, with rounded angles. Dorsal small, low, highest in the middle 



