The sturgeons are sluggish, clumsy, bottom-feeding fish. The mouth, underneath the long snout, is very protractile, sucker-like, and without teeth. Before it on the under side of the snout are four long feelers. Ordinarily the sturgeon feeds on mud and snails with other small creatures, but I have seen large numbers of Eulachon (_Thaleichthys_) in the stomach of the Columbia River sturgeon (_Acipenser transmontanus_). This fish and the Eulachon run in the Columbia at the same time, and the sucker-mouth of a large sturgeon will draw into it numbers of small fishes who may be unsuspiciously engaged in depositing their spawn. In the spawning season in June these clumsy fishes will often leap wholly out of the water in their play. The sturgeons have a rough skin besides five series of bony plates which change much with age and which in very old examples are sometimes lost or absorbed in the skin. The common sturgeon of the Atlantic on both shores is _Acipenser sturio_. _Acipenser huso_ and numerous other species are found in Russia and Siberia. The great sturgeon of the Columbia is _Acipenser transmontanus_, and the great sturgeon of Japan _Acipenser kikuchii_. Smaller species are found farther south, as in the Mediterranean and along the Carolina coast. Other small species abound in rivers and lakes. _Acipenser rubicundus_ is found throughout the Great Lake region and the Mississippi Valley, never entering the sea. It is four to six feet long, and at Sandusky, Ohio, in one season 14,000 sturgeons were taken in the pound nets. A similar species, _Acipenser mikadoi_, is abundant and valuable in the streams of northern Japan. [Illustration: FIG. 7.—Lake Sturgeon, _Acipenser rubicundus_ Le Sueur. Ecorse, Mich. ] In the genus _Acipenser_ the snout is sharp and conical, and the shark-like spiracle is still retained. [Illustration: FIG. 8.—Shovel-nosed Sturgeon. _Scaphirhynchus platyrhynchus_ (Rafinesque). Ohio River. ] The shovel-nosed sturgeon (_Scaphirhynchus platyrhynchus_) has lost the spiracles, the tail is more slender, its surface wholly bony, and the snout is broad and shaped like a shovel. The single species of _Scaphirhynchus_ abounds in the Mississippi Valley, a fish more interesting to the naturalist than to the fisherman. It is the smallest of our sturgeons, often taken in the nets in large numbers. In _Scaphirhynchus_ the tail is covered by a continuous coat of mail. In _Kessleria[6] fedtschenkoi_, _rossikowi_, and other Asiatic species the tail is not mailed. Footnote 6: These species have also been named _Pseudoscaphirhynchus_. _Kessleria_ is the earlier name, left undefined by its describer, although the type was indicated.