PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 35 



32. Raia binoculata Girarcl. — Skate; Bay. 



{Baia cooperi Grd.) 

 From Monterey to Alaska; everywhere common ; the largest and most 

 abundant skate on the coast. It frequents bays and sandy shores, and 

 is taken with nets or hooks. It feeds on crustaceans and fishes. Two 

 specimens of Cottus polyacanthocephalus, each a foot long, were found in 

 the stomach of one of these skates. The egg-cases are laid in July. 

 They are quadrate, with very short tentacles, and are nearly a foot in 

 length. Baia binoculata reaches a length of 5 to 6 feet and a weight of 

 more than 00 pounds. It is generally the commonest species in the 

 markets of San Francisco; elsewhere it is rarely used for food, and its 

 liver yields but very little oil. 



Family TRYGONID^. 



33. Urolophus halleri Cooper. — Bound Sting Bay. 



From Point Concepcion southward ; excessively abundant in the bays 

 and lagoons. The bottom of portions of San Diego Bay is literally lined 

 with these rays, who lie on the bottom nearly buried in loose sand or 

 mud. This is the smallest, most abundant, and most dangerous of the 

 sting-rays, striking quickly and accurately with its muscular tail. One 

 taken in a net struck at another, the sting passing entirely through the 

 body of the latter. This species reaches a length of 18 inches, and is 

 never eaten. 



34. Pteroplatea marmorata Cooper. — Bay. 



From Santa Barbara southward ; common in bays and along sandy 

 shores. It reaches a length of Ih feet, the breadth being about 2i. It 

 is not usually recognized as a sting-ray, and is, therefore, frequently 

 used as food, the larger ones taken at San Pedro being shii)i)ed to Los 

 Angeles, where they are eaten by the French as Eaie. 



35. Dasybatus dipterurus Jordan & Gilbert. 



Abundant in San Diego Bay; not seen elsewhere. It reaches a 

 length of nearly 3 feet, exclusive of the tail. It is not used as food. 



Family MYLIOBATID^. 



36. Myliobatis californicus Gill. — Stlngaree; Sting Bay. 



{Bhinoptera vespertiJio Grd.) 



From Cape Mendociao' southward; very abundant, especially about 

 San Diego. Like the other species of sting-rays, it feeds on fishes and 

 Crustacea, and takes the hook readily. Its young are brought forth in 

 July. It reaches a weight of GO pounds or more, and is sometimes 

 brought into the market of San Francisco. 



37. Aetobatis laticeps Gill. 



California and southward ; not obtained by us. 



