168 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [462] 
fishes. It is true that many of the larger fishes frequent the estuaries 
to prey upon smaller ones, some of which are extremely abundant in 
these waters. But the small fishes, like minnows, as well as the young 
of the larger ones, feed chiefly upon the small crustacea, worms, and 
shells that live in the waters that they inhabit. Therefore the entire 
value of the estuaries as feeding-grounds for the larger fishes depends 
directly upon those species of crustacea, &c., that naturally live in 
brackish water. 
In discussing the fauna of the estuaries I have found it most conven- 
ient to group the species under the following divisions: 1. Those of sandy 
shores and bottoms. 2. Those of muddy shores and bottoms. 5. Those 
inhabiting oyster-beds. 4. Those inhabiting the eel-grass. 5.. Those 
attached to rocks, piles of wharves, floating timber, buoys, &e. 
The lists could be greatly extended by ineluding all the species to be 
found near the mouths of estuaries, or in those harbors and ponds that 
are scarcely brackish, for in these localities the fauna is nearly identi- 
cal with that of the bays and sounds, and the lists already given on 
previous pages will also apply very well to such places. 
As a general rule only those species that are abundant, or at least 
frequent, in waters distinetly brackish, have been included in the lists. 
III, 1—ANIMALS INHABITING THE SANDY SHORES AND BOTTOMS OF 
BRACKISH WATERS. 
Sandy shores and bottoms are generally less common and less exten- 
sive than muddy ones, and occur chiefly toward the months of estuaries, 
or on the more exposed borders of the larger ponds and harbors, where 
the wave-action is greatest. 
When such bottoms are covered with eel-grass, as often happens, the 
animals are quite numerous, but when destitute of vegetation the spe- 
cies of animals are but few, and mostly of the kinds that burrow. But 
when there is a mixture of mud with the sand the variety is much 
greater. 
Near high-water mark, colonies of the “ sand-fiddler,” Gelasimus pu- 
gilator, (p. 336,) often occur, as on the sandy beaches outside. In the 
same situations the beach-fleas, Talorchestia longicornis and T. megal- 
ophthalma (p. 336,) also occur, burrowing in the sand; while the Orches- 
tia agilis SMITH is abundant under the vegetable débris at high-water 
mark. : 
Several species of salt-water insects also occur, burrowing in the 
sandy beaches at and below high-water mark. Among these are sev- 
eral beetles, which live in such situations, both in the larval and adult 
conditions. The Bledius cordatus is one of the most abundant of these. 
This is a small, dark-colored, “ rover-beetle,” with very short elytra. 
It makes small, perpendicular holes in the sand near high-water mark, 
throwing up a little mound of sand around the burrows. <A larger spe- 
cies, Bledius pallipennis, occurs lower down, at about half-tide mark 
and makes similar burrows, but they are larger and deeper. This spe- 
