88 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 
it is this latter form which is very rare, both absolutely and relatively. 
Formerly they were more common, but about twenty or twenty-five 
years ago the old Russian Company resolved to pay more for the white 
ones than for the blue, and to have them killed all the year round 
without respect to the season, in order to destroy them and possibly 
have them exterminated. . At present they are very scarce, and now 
the natives themselves pursue them eagerly, because they spoil the 
brood by mixing with the blue ones.* 
From the following list it will be seen that the number of foxes de- 
creases greatly when they are hunted for several successive years. It 
has therefore been agreed upon that the hunt be suspended for one or 
two years, with intervals according to circumstances, in order to give 
the animals time to fill the diminished ranks. This may perhaps be 
the cause of Nordenskjold’s mistake. The fact is, that the fox hunting 
is a very important source of income to the natives on Bering Island. 
Number of foxes killed on Bering Island. 
| 
Season. Blue foxes. | White foxes. 
VO FMD of om br seia a tein icieipln tare Saieeo ea eae cole oeew alee soem sicete sarees ee eet 836 4 
28 
24 
0 
50 
19 
0 
0 
0 
0 
20 
145 
*No foxes hunted during the season in question. 
I ought not to omit mentioning two other terrestrial mammals which 
offer a contribution to the history of the immigration of the fauna. The 
one is Mus musculus L., the other Arvicola rutilus Pall. 
According to the assertion of the inhabitants, it is beyond any doubt 
that none of these animals occurred on Bering Island before 1870. 
Before that time they had not even seen a mouse, and many of them 
had never heard the name mentioned. In 1880 the “black mouse” 
(musculus) was brought from San Francisco by the schooner ‘“‘ Justus,” 
with a cargo of flour. The ‘red mouse” (rutilus) made its appearance 
later, but as the natives were then already acquainted with that kind 
of animal, they did not pay sufficient attention to ascertain in what 
year the introduction actually took place. That 1t was introduced later 
than the common mouse is proved by the belief of the natives, who 
think that the red, short-tailed mouse is the offspring of the long-tailed, 
dark-colored animal. It: finally turned wild by changing its more 
domesticated manner of life into the freer habits in the fields and moun- 
~ *On Copper Island white foxes do not appear at all, Besides, the blue ones are 
said to be larger, which is probably caused by a larger supply of food. 
