1432 



ZOOLOGICAL SOCIKTY BULLETIN 



seven inches in length. These fishes are dis- 

 tributed among the tanks containing dog sharks, 

 to which they may be seen clinging in charac- 

 teristic fashion. When there are no fishes pres- 

 ent to which they may cling, they attach the 

 head disc to the walls and glass fronts of the 

 tanks, or even turn over and attach upside down 

 to the tank bottom. The appearance of the ce- 

 phalic disc is well shown in the accompanying 

 photograph of the fish clinging to glass. In the 

 photograph of the two nurse sharks, the small 

 fishes present are shark suckers. 



FEEDING HABITS OF THE STURGEON. 

 By W. I. DeNyse. 



THE sturgeon {Acipenser sturio) , is one of 

 the largest food fishes caught in our wa- 

 ters, and sometimes reaches a weight of 

 500 pounds and a length of 10 feet. Its food 

 consists of mollusks, crustaceans, and algae, and 

 sometimes small bottom fishes are found in its 

 stomach. 



Its method of feeding is unique. Underneath 

 the snout, and near the point of it, are four 

 barbels about two and one-half inches long, 

 placed about three-quarters of an inch apart 

 across the snout. It swims with the snout close 

 to the bottom, allowing the barbels to trail along 

 on the sand or mud. 



Whenever these barbels touch the protruding- 

 siphons of the soft shelled clam or razor clam, 

 the siphons of the clams contract, and by doing 

 so, notify the sturgeon of their presence. It 

 halts, and with its telescope mouth pumps the 

 sand or mud away from the clam, passing it out 

 of the gill openings, and finally drawing the 

 clam from its home in the sand or mud up into 

 the jaws where it is crushed. The larger por- 

 tions of shells are discarded through the gill 

 openings. If the clams are small, very little of 

 the shell is discarded, all going into the stomach. 

 Another way the sturgeon has of feeding is 

 to plough a furrow through the sand or mud 

 with its long pointed snout, then turning around 

 and going back through the furrow, it picks up 

 small mollusks and crustaceans it has thus ex- 

 posed. The sturgeon also will suck up with 

 its protruding mouth great quantities of sand 

 and mud, sifting it through the gills, and by so 

 doing finds many small organisms upon which 

 it feeds. 



The Tile-fish in the Markeis— The United 

 States Bureau of Fisheries reports the quantity 

 and value of tilefish landed at the port of New 



Photograi.h b\- EKvin R. Sanborn 



SHARK SUCKER CLINGING TO GLASS 



York during the months of August and Septem- 

 ber at 2,400,000 pounds, valued at $80,590. 

 The price per pound ranged from two to six 

 cents. 



