80 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
night herons, marsh hawks, and one hsh hawk visited the island 
during my stay but none bred. Mr. Sandsbury told me, however, 
that the crows sometimes build their nests on the chimneys of the 
fishing huts. The short-eared owls mentioned by Mr. Brewster have 
disappeared. 1 The two mammals inhabiting Muskeget are the 
white-footed mouse and the beach mouse. The former is rather 
common in the clumps of beach plum bushes and about the numerous 
small houses along the south side of the island. Specimens do not 
differ appreciably from those of Peromyscus leucopus taken on 
Nantucket, though occasionally one occurs in a very peculiar half¬ 
white coat. These pallid specimens, however, do not occur often 
enough to make the Muskeget Peromyscus worthy of recognition 
as a local race of leucopus. 
The other Muskeget mammal, Microtus breweri , was formerly very 
numerous. Mr. Allen speaks of it as “ excessively abundant ” in 
1869, and Mr. C. J. Maynard who visited Muskeget with Mr. Allen 
has often told me of the myriads of mice then on the island. In 
1891, however, Mr. Wm. Brewster was unable to find any trace of 
them. Prior to 1891 the last persons to see Microtus breweri on 
Muskeget were Mr. F. H. Kennard and Dr. C. S. Francis who 
observed a few during the summer of 1890. 2 Mr. John R. Sandsbury 
of Nantucket, who spends the summer on Muskeget to enforce the law 
protecting the terns and who has been familiar with the beach mice for 
many years, says that during 1890 or 1891 the animals disappeared 
completely. Mr. Sandsbury attributes the extinction of the mice 
to the work of cats that ran wild on the island after the burn¬ 
ing of the U. S. Life Saving Station a few years before. This 
hypothesis is probably correct, since the mice, through their inability 
to burrow in the loose sand, are peculiarly exposed to the attacks of 
predatory animals, while the colonies that chanced to be isolated on 
South Point Island and Adams Island out of reach of the cats sur¬ 
vived in a flourishing condition, thus proving the disappearance of 
*1 found, however, on South Point Island an owl’s pellet made up of fur and bones of 
Microtus bretveri. In the Auk for January, 1896, (p. 88), Mr. George H. Mackay records 
a nest of Asio accipitrinus found by Mr. Sandsbury, among the beach grass at the 
northeast side of Muskeget on June 2,1895. It contained two downy young. 
2 On June 6,1894, Mr. Kennard wrote me as follows: “Dr. C. S. Francis with whom 
I visited Muskeget from June 25 to 29,1890, corroborates my statement with regard to 
the mice on Muskeget proper. While we saw numbers of them on South Point Id., 
we did see a very few in the middle of Muskeget. I was a trifle in doubt on this point, 
but Dr. Francis is positive. We noticed the marked difference in the number of mice 
on South Point Island and on Muskeget and laid it to the cats.” 
