22 FISHES OF ILLINOIS 



the coasts of both Europe and America. The shovel-nosed 

 sturgeons are represented in the waters of the Mississippi Valley 

 by two species. Three species of the genus Pseudoscaphi- 

 rhynchus, resembling more or less the American shovel-nosed 

 forms, are confined to small tributaries of the Aral in Tartary. 

 Fossil Acipenseridoe are little known, though numerous scutes 

 have been described from Tertiary formations of Europe and 

 America. Some species of sturgeon reach an immense size, 

 specimens of the great Russian sturgeon (A. huso) having been 

 taken weighing more than 3,000 lb. A. rubicundus, of the North 

 American Great Lakes, reaches a length of four to six feet. The 

 smallest of the species of Acipenser, the sterlet {A. ruthenus) of 

 Europe, reaches three feet in length. 



Sturgeons are bottom feeders, using their hard beaks to 

 stir up the mud in their search for food. Stomachs of sturgeon 

 have been found to contain worms, mollusks, insect larvae, 

 small fishes, and aquatic plants. In feeding, the mouth is pro- 

 truded downwards, spout-like, and thrust into the mud. The 

 sensitive barbels and papillose lips doubtless assist in locat- 

 ing objects of food, although the intestines are generally more 

 or less filled with mud, swallowed with the organisms it con- 

 tains. Schools of sturgeon have been observed in clear water 

 along the coasts digging up the soft bottom of shallows with 

 their snouts, in search, no doubt, of mollusks and other organ- 

 isms. Sturgeons are ordinarily captured with gill-nets and set- 

 lines, though seines and pound-nets, set for other fish, are said 

 to take them in considerable numbers. 



Their breeding season is in spring, as a rule from the first to 

 the last of May. The eggs of all species very quickly become 

 glutinous and adhere to sticks, weeds, and other objects. The 

 incubation period of the Atlantic sturgeon is about 7 da3^s in 

 water at 62° to 65° Fahr. The 3^oung live on the yolk alone up 

 to a length of ^ inch, and from that size to 5 inches they feed 

 on rhizopods, algae. Infusoria, and minute larvae. 



The flesh of all sturgeon, excepting the small shovel-nosed 

 forms of Asia, is used as food, and from the eggs of the larger 

 kinds caviar is prepared. If eaten fresh the flesh, except of 

 young specimens, is usually found to be rather coarse and beefy, 

 and in consequence sturgeon are as a rule smoked or boiled in 

 vinegar before being sold Smoked sturgeon is now considered 

 scarcely inferior to halibut, and the demand for it is increasing. 

 The consumption of smoked sturgeon in the United States was 



