LEPORIDZ—EPIDEMIC DISEASES. Sk 
of 
or from the severity of the weather, if they do not actually excavate them 
themselves. ‘This is a well-known habit, in many localities, of our common 
so-called Gray Rabbit (Z. sylvaticus), and also of the Lepus campestris, or 
so-called Prairie Hare. At localities where LZ. americanus and L. sylvaticus 
occur together, the former is often designated as the Hare and the latter as 
the Rabbit. Perhaps, however, the one is oftener called White Rabbit and 
the other Gray Rabbit. Gray Rabbit, perhaps from long familiarity with the 
same, seems to sound more euphonious than Gray Hare; Marsh Hare than 
Marsh Rabbit; and Jack Rabbit or Jackass Rabbit than Jack Hare or Jackass 
Hare; and, however philologically or technically wrong it may be to apply the 
term Rabbit to any of our wild species, the custom of so doing among the 
generality of our people is doubtless as ineradicably fixed as is that of calling 
the American Bison a Buffalo. 
EPIDEMICS AMONG THE NORTH AMERICAN SPECIES OF HARES. 
Nothing is better known to attentive observers of our Mammals than 
the fact that certain species, especially of the Rodentia, are for a period of 
years often exceedingly abundant, these periods being followed by succeeding 
years of scarcity. This is especially observable among the Field Mice (partic- 
ularly in the case of Arvicola riparius), the Squirrels, and the Hares. Their 
decrease results usually from some not very obvious cause, though sometimes 
supposed to be connected with a series of unusually severe winters. That 
this is not the sole cause of their decrease I have been for a long time con- 
vineed, but that it is due more to some prevalent epidemic. ‘The evidence 
of this is not generally easily obtainable, but proof of it in other cases is 
quite abundant. In the case of our little Wood Hare (Lepus sylvaticus), I 
have repeatedly met with their dead bodies in the woods and thickets, bear- 
ing no mark of a violent death, and noted the scarcity of these animals during 
the years immediately following. I have also observed the same thing in 
respect to our common Meadow Mouse (Arvicola riparius). I find also 
recorded in my notes a remarkable decrease, some years since, of the large 
Long-eared Hares (ZL. callotis var. texianus and L. campestris) in the Great Salt 
Lake Valley. This decrease was also accompanied by the finding of great 
numbers of the animals dead on the Sage-brush plains about the lake, showing 
no signs of a violent death (of which fact I was abundantly assured by the 
residents of the region in question), leading to the conclusion that their death 
