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of aquatic plants. It seeks its food under the ice, and evidently carries 
it to its burrows. No large stores are observed in its burrows, however, 
but only roots recently carried in. The summer food consists of leaves of 
various aquatic plants, and different species of river muscles. Every one 
at all familiar with the shallows of our streams, will recall the immense 
heaps of muscle shells, often a bushel or more, by the side of some large 
stone or log, midway perhaps of the river, and furnishing easy collecting 
grounds for the conchologist. These are the ‘‘oyster restaurants” of the 
Muskrat. Collecting the muscles from the river bottom, the Muskrat 
mounts the log or stone, sits up on its haunches like a Squirrel, and 
opens the shell with its strong incisor teeth, as neatly as a Squirrel 
opensa nut. Most of the shells are left with the ligament intact. Mr. 
Kennicott has found massive shells, like those of Unio plicatus, left un- 
opened, or with the valves gnawed apart at the back. 
The Muskrat is pugnacious, fights when captured, and the males often 
have fierce battles among themselves. The Mink is its worst enemy, en- 
tering its houses and burrows, and pursuing it in the.water. 
From five to seven young are produced in April or May.’ 
Muskrats are seldom injurious to crops; sometimes they take to vegeta- 
ble gardens, showing a commendable weakness for parsnips and muskmel- 
lons. They are sometimes destructive to growing corn, which they cut 
off and sink into the water, probably to eat at their leisure. With the 
exception of the mollusks already referred to, and the occasional eating 
of a dead fish, they do not depart from a vegetable diet. 
Their depredations on canal banks, mill dams, and ice ponds are well 
known. Along the line of the Illinois and Michigan canal, the “canal 
walkers” are compelled to keep a sharp eye to the Muskrats, lest they 
burrow through the bank, and trappers, with their boats, are passed 
through the locks and given the right of way along the tow-path. 
Mr. Kennicott states that “hunters and trappers consider the hind- 
quarters cf the Muskrat very palatable, when roasted on coals ; and they, 
as well as the Indian, esteem the tail a great delicacy. 
FAMILY HYSTRICIDA. 
The American Porcupines, sub-family Synetherinx, differ from the Old 
World Porcupines, sub-family Hystricine, in the form of skull; in having 
the clavicles perfect, the tail (except in Hrethizon) more or less prehen- 
sile, the molar teeth fully rooted; in not having five toes toall the feet 
(usually four, both before and behind); in the tuberculated, instead of 
smooth soles; in the upper lip being undivided by a vertical groove; 
