264 LAKE SUPERIOR. 



withstanding their extraordinary peculiarities, they are more closely 

 related to the gar-pikes, than to any other group of fishes. This 

 view, though at first strongly opposed, is now generally admitted, 

 having been sustained both by anatomical and palgeontological 

 evidence. 



The sturgeons are generally large fishes, which live at the bot- 

 tom of the water, feeding with their toothless mouths upon decom- 

 posed organized substances. Their movements are rather sluggish, 

 resembling somewhat those of the codfish tribe. 



Their geographical distribution is quite peculiar, and constitutes 

 one of their prominent peculiarities. Located as they are, in the 

 colder portions of the temperate zone, they inhabit either the fresh 

 waters or the seas exclusively, or alternately both these elements, 

 remaining during the larger part of the year in the sea, and ascend- 

 ing the rivers in the spawning season. Although adapted to the 

 cold regions of the temperate, they do not seem to extend into 

 the arctic zone, and I am not aware that they have been observed in 

 any of the waters of the warmer half of the temperate zone. The 

 great basin of salt water lakes or seas which extends east of the Med- 

 iterranean, seems to be their principal abode in the Old World, or at 

 least the region in which the greater number of species occur ; and 

 each species takes a wide range, extending up the Danube and its 

 tributaries, and all the Russian rivers emptying into the Black 

 Sea. From the Caspian they ascend the Wolga in immense 

 shoals, and are found farther east in the lakes of Central Asia, 

 even as far as the borders of China. The great Canadian lakes 

 constitute another centre of distribution of these fishes in the New 

 World, but here they are neither so numerous, nor do they ever 

 occur in contact with salt water in this basin. 



Northwards, there is another great zone of distribution of stur- 

 geons, which inhabit all the great northern rivers emptying into the 

 Arctic Sea, in Asia as well as in America. They occur equally in 

 the intervening seas, being found on the shores of Norway and 

 Sweden, in the Baltic and North Sea, as well as in the Atlantic 

 Ocean, from which they ascend the northern rivers of Germany, as 

 well as those of Holland, France, and Great Britain. Even the 

 Mediterranean and the Adriatic have their sturgeons, though few 



