5*4 
GANOIDS. 
on the upper lobe of the tail, as we thus have evidence of the descent of the family 
from fully scaled fishes. 
Toothless From the preceding family the typical sturgeons ( Acipenseridce ) 
sturgeons. m ay be distinguished by the absence of teeth in the adult, and the 
presence of live longitudinal rows of bony plates on the naked body, which is 
elongate and subcylindrical in form, as well as by the presence of four barbels in a 
transverse line on the under surface of the muzzle. The muzzle is somewhat 
produced, and either subspatulate or conical in form, with the small, transverse 
mouth on its lower surface. All the vertical tins are armed with a single series of 
fulcra on their front edges; the dorsal and anal are situated at a moderate distance 
from the caudal; and the large air-bladder is simple. Confined to the temperate 
regions of the Northern Hemisphere, sturgeons are either exclusively or partially 
fresh-water fish, some of them only ascending rivers for the purpose of spawning, 
after which they return to the sea. With the slender-beaked sturgeon, they 
include the largest fresh-water fishes of this region, several of the species commonly 
growing to 10 feet, while some are much larger. The females deposit enormous 
numbers of extremely minute eggs, the product of a single individual having been 
estimated at upwards of three millions during a season. This wonderful fecundity 
easily accounts for the enormous numbers in which sturgeon, in spite of constant 
persecution, still crowd the northern rivers during the spawning-season. In 
addition to the excellence of their flesh, sturgeon are valued for their roe, from 
which is manufactured caviare, and for their air-bladder, the inner coat of which 
forms the basis of isinglass. In a fossil state sturgeons are unknown before the 
upper part of the Eocene period. All the members of the genus are exceedingly 
voracious fishes, and the majority are mainly carnivorous. During the winter 
many or all of them crowd together, either in inlets of the sea, estuaries, or the 
deep pools of rivers, where they undergo a kind of hibernation; and it is stated 
that in some localities they bury their noses in the mud, with their bodies and tails 
standing vertically upwards like a series of jDOsts. They increase very rapidly in 
size; and the eggs are hatched in five days. Although still abundant in the 
northern rivers, in those of Central Europe sturgeon have greatly decreased in 
numbers, and few really big fish are now taken. In the beginning of the year, 
when they are still torpid, sturgeon are captured by breaking the ice, and stirring 
up the mud at the bottom of their haunts with very long poles armed with barbed 
prongs. As the fish seek to escape, some are stabbed with the spears; and it is 
said that half a score of large fish may be thus taken by a single fisherman. In 
summer regular fishing-stations are established on the Russian rivers, where the 
approach of a shoal is heralded by a watchman. Upwards of fifteen thousand 
sturgeon have been taken in a day at one of these stations; and when the fishing 
is suspended for a short time, a river of nearly four hundred feet in width, and 
five-and-twenty in depth has been known to be completely blocked by a solid 
mass of fish. 
„ The common sturgeon (Acipenser sturio), of which a small 
True Sturgeons. . . ” . x . ' 
example is shown in the illustration facing p. 510, is the typical 
representative of the first genus, in which the rows of bony plates remain distinct 
from one another on the tail, spiracles are present on the head, the upper lobe of 
