STURGEONS. 
153 
But ty the evidence of an intelligent fisherman, reported by 
Gcsner, these plates are also on some occasions converted 
into weapons of offence; and he had seen them used as such 
against the Huso, another fish of this family, of a still larger 
size than the Common Sturgeon but of a very timid nature, 
and against which the latter species is supj)osed to bear an 
instinctive animosity. The skin of the Huso is without any 
of those plates with which others of this family are defended, 
and it has been seen therefore to suffer severely firom the rough 
treatment of those cutting and tearing instruments brought 
into action by its enemy, from which it has sought in vain to 
escape by plunging in all directions. 
Nor is the internal organization of this family of fishes less 
a departure from the usual type of the Sharks, while still 
here also remains some degree of likeness, at least in the 
presence of a spiral valve to the intestine; by which organi- 
zation the functional power is lengthened out, whilst the bulk 
of the organ is packed into the smallest space its nature 
admits of. 
These fishes neither deposit their eggs in purses nor pro- 
duce fjrcir young alive; but their roe consists of small grains, 
which they shed in the same manner as bony fishes, in the 
fresh- water of the larger rivers ; which they enter for that 
purpose, and in particular districts, especially of the south of 
Russia and the Caspian Sea, in enormous multitudes, in con- 
sequence of which extensive and fiourishiiig fisheries are 
established for taking them. Their productiveness may be 
judged from the fact that, according to Pallas, ( Second Travels, 
voll i,) of the three species fished for seventeen hundred and 
fifty thousand have been caught in one year. Fifteen thousand 
have been taken in a day by one method of fishing, and, 
what is still more remarkable, if the fishermen should have 
been accidentally prevented from working during a single day, 
the fish have been known to accumulate in such numbers at 
the weir, as to fill the whole channel; insomuch that those 
which were uppermost appeared with their backs above water, 
in a river not less than twenty-eight English feet deep, and 
sixty fathoms wide. 
With such numbers it may be concluded that Sturgeons of 
the different sorts are highly prolific; and Adolph Erman, in 
VOL. I. z 
