THE STURGEONS AND STURGEON INDUSTRIES. 
265 
gauisins upoa which the sturgeon is directly or indirectly dependent must therefore 
be obvious to every one. The legitimacy of the inquiries into the life-histories of all 
organisms, even those in no way directly related to the economy of the State, should 
therefore need no apology from those engaged in the study of the problems of economic 
fish-culture. 
10. HABITS OF THE STURGEON. 
The habits of this fish, as might in fact be inferred from the conformation of the 
head and mouth, are essentially those of a scavenger and bottom feeder. The tooth- 
less, protusible mouth of the adult is in itself sufficiently suggestive of the mode in 
which a very large proportion of its food must be taken, notwithstanding the state- 
ments made by some European observers that the sturgeon may even rise to the 
surface to seize from beneath and swallow, in an entire state, such unwary water- 
birds as may be disporting themselves there. That the young do pursue, capture, and 
swallow rather active prey is proved by the fact that great numbers of the exoskele- 
tons of amphipod crustaceans are found, together with other ingesta, in the region of 
the hind gut, modified to form a spiral valve. Whether these amiihipods are taken 
while the sturgeons are swimming about through the water some distance from the 
bottom is uncertain, though it is probable that the young fish take them at the bot- 
tom, from the fact that large quantities of mud are found associated in the intestine 
with the remains of the crustaceans. 
Adult sturgeons are frequently encountered, in the iutestine of which the broken 
fragments of the shells of mollusks, bivalves as well as univalves, are met with. 
Fragments of Mytilus and other brackish-water forms are found in the alimentary 
tract of such individuals. This dietary is sufficiently indicative of the mode in which 
the animals take their food, and it is probable that annelids, nemerteaus, etc., also 
enter largely into the dietary of these fishes. I have also met with the remains of 
earth worms in the iutestine of young sturgeons. 
The mechanism by means of which the sturgeon is made aware of the presence 
of the living forms at the bottom consists of a transverse row of four pointed, highly 
sensitive barbels, which are placed about half way between the tip of the snout and 
the mouth. In the j'ouug these barbels are more slender and proiiortionally longer 
than in the adult, in which they present a series of transverse incisures or laminm 
ranged side by side, and which are covered by a sensitive, tactile epithelium. This 
apparatus supplements the soft sensitive lobes which surround the entrance to the 
mouth more or less completely, and constitute a system of organs of touch by the help 
of which the animal is made aware of the jireseuce of the living food at the bottom 
upon which it subsists. 
The snout of the adult sturgeon appears to be used more or less after the manner 
of a digging implement. Mr. Eikington informs me that at Tampa Bay in Florida 
the schools of sturgeons may be observed near the shore digging up the soft bottom of 
shoal places with their snouts. The object of such a habit would seem to be the 
search for half-buried mollusks, annelids, etc., which are doubtless swallowed, to- 
gether with more or less dirt, as we saw in the case of the amphipods taken by the 
young animals. My informant also stated that the Florida sturgeons had a, sliorter, 
more recurved snout than those of the Delaware. Whether this difference is merely 
