STURIONES I STURIONID/E. 



355 



Fig. 235. 



ered with regular bony plates, 



soldered in such a manner as 



to form an inflexible shield, so 



that the mouth, tail, and fins 



are the only movable parts. 



Thirty or more species are 



known, inhabiting tropical and 



temperate seas. The Genus 



Lactophrys contains two or more species, from three and 



a half to fourteen inches long, which are found on the 



Atlantic coast of the United States. 



Trunk-Fish, L. camelimis, Dekay. 



SUB-SECTION VII. 



THE ORDER OF STURIONES, OR STURGEONS. 



THIS Order embraces cartilaginous fishes with free 

 gills, and one large external opening on each side, with a 

 strong operculum. 



STURIONID/E, OR STURGEON FAMILY. This Family 

 contains those which have large bony plates arranged in 

 longitudinal rows, the mouth under the snout, without 



Fig. 236. 



Sturgeon, A. oxyrhynchus, Mitch. 



teeth, and very protractile, and the lobes of the tail un- 

 equal. The Genus Acipenscr contains the Sturgeons 

 proper. They inhabit lakes and the sea, and ascend the 

 rivers of many countries. The Sharp-nosed Sturgeon, A. 

 oxyrhyncJius, Mitch., of the Atlantic coast of North Amer- 

 ica, is from four to eight feet long. The Lake Sturgeon, 

 A. rubicundus, LeS., of the Great Lakes, is about four 

 feet long, and of a ruddy hue. Several other species be- 

 long to North America. The Great Sturgeon, A. huso, 



