932 
FOREST AND STREAM. 
• [June 12, 1909. 
nailed a lot of fish hooks on the pole to dis¬ 
courage cats, and these were all gone, and I 
thought the boys had taken advantage of the 
dog's absence. But last March, when I cleaned 
out the old sparrows’ nests, I found five dead 
martins in one compartment. Two were quite 
good size and three smaller, but the growth of 
the feathers showed that all were young birds. 
What caused their death is a mystery to me. 
Perhaps some one of your readers can enlighten 
us? Before this we never had more than three 
young birds to a family. 
I think there are more martins down town than 
in the residence district, and I am never on the 
streets in the business district during the sum¬ 
mer, but that I can hear them chattering. They 
are a very graceful bird on the wing, and we 
never tire of watching them. 
The amount of insects they consume must be 
enormous. I have seen the old bird come in 
with a devil's darning needle, almost as big as 
herself, and ram it down the youngster's throat, 
wings, legs and all, until I wondered why the 
little fellow was not choked to death. 
J. W. G. D. 
Osgood on the Wood Mice. 
An animal well known to most outdoor men 
and women is the little wood mouse, known also 
as deer mouse, vesper mouse, or white-footed 
mouse, which lives out of doors and often builds 
its nest of shreds of cedar bark in the briars at 
the height of a man's head, or even takes pos¬ 
session of deserted birds’ nests. Hcsferomys 
we used to call him, but now his name has been 
changed to Pcromyscus, and Wilfred H. Osgood, 
of the Biological Survey, has just published a 
revision of the mice of that genus. This forms 
No. 28 of North American Fauna and is a 
volume of more than 280 pages, beautifully illus¬ 
trated by a colored map showing the distribu¬ 
tion of the different forms of Pcromyscus, six 
plates of skulls and one of the teeth and feet— 
eight plates in all. 
The genus is very abundant over much of the 
country of North America to which it is peculiar. 
The colored map shows that in one form or 
other it is found from Labrador to Alaska, north 
to well within the Arctic circle and south as far 
as Southern Mexico. In the interior it is very 
abundant, inhabiting deserts as well as forests. 
Everywhere the forms are so similar that it 
would take a trained biologist to identify the 
particular form which he might meet with. The 
habits of the various forms differ widely. Those 
which, like our local white-footed mouse, in¬ 
habit woodlands live in one way, others found 
in swamps and along watercourses or on open 
upland prairies, among rocks and cliffs, or in 
arid deserts, have adapted their ways to their 
surroundings. While some of them perhaps 
occupy burrows, others live in underground 
natural openings or in retreats which other 
animals have made. Some prairie forms are 
said to make short burrows and to build their 
nests in them. Some of these mice, as already 
suggested, often climb far above the ground. 
The woodland species may build their nests in 
old stumps and hollow trees, may occupy nesting 
cavities dug out by woodpeckers, or may take 
advantage of some natural cavity in a tree trunk. 
We once entered the large front room of an 
unoccupied house in New Jersey and saw in 
the middle of the room on the bare floor the 
globular nest of one of these mice and the parent 
sitting by it. They are chiefly nocturnal in habit, 
as might be inferred from the size and promi¬ 
nence of their brilliant eyes. 
While sometimes in countries where the house 
mouse has not yet penetrated, the white-footed 
mouse will take possession of the settler’s cabin, 
yet they are not very fond of an indoor life. 
Nevertheless the easy method of getting food 
is a strong temptation to them. They do not 
seem to occupy houses where the house mouse 
has established itself. When they do take up their 
abode in house they do a great deal of damage, 
“cutting up fabrics for nest materials, destroy¬ 
ing all kinds of food stuff and doing much dam¬ 
age about granaries, straw or haystacks or out¬ 
buildings. In the interior of Canada they invest 
trappers’ lonely cabins and levy tribute on the 
provisions, and at trading posts they enter ware¬ 
houses and damage the merchandise.” They can 
be destroyed by the same methods that would 
be used on the house mouse by trapping or poi¬ 
soning. 
This mouse is omnivorous and forages exten¬ 
sively in the kitchen after he has once taken 
up his home under a roof. They carry off grain 
and make caches of it when they can, and nearly 
all prefer dry, rather than succulent, food—espe¬ 
cially seeds and small nuts. The common form 
of the Northeastern United States is fond of 
bass wood seeds, pits of wild cherries, beech 
nuts and acorns and often stores them up. 
Kennicott has recorded in one of the old agri¬ 
cultural reports that in Western New York there 
was found ‘‘within a stump in a clover field sev¬ 
eral quarts of clean seed of red clover collected 
by a family of these mice.” The deer mice are 
sometimes charged with gnawing the bark of 
young fruit trees or nursery stock, but it is 
possible that this charge is unjust and that such 
harm is more often done by meadow mice. The 
Western forms, which inhabit open ground, may 
do more damage to the crops than do the East¬ 
ern forms, which are more or less woodland 
species. The Western species often live in cul¬ 
tivated fields and perhaps do considerable injury. 
Their numbers are vast, and if they devoted 
themselves entirely to the crops they would do 
an enormous amount of damage. They are very 
prolific, bear from four to six young in a litter 
and breed through the entire year. It is prob¬ 
able that a large part of their food maj' be the 
seeds of noxious weeds and that in this way 
they do a great deal of good. Perhaps also 
they devour insects to some extent. 
While the white-footed mice are less injurious 
than the voles or meadow mice they are to be 
regarded as vermin and their undue increase 
should be checked. Their natural enemies are 
hawks and owls, but owing to their nocturnal 
habits owls are their greatest enemies and should 
be protected by law. 
Mr. Osgood’s revision of this very important 
genus is based on a study of more than 27,000 
specimens representing the collections of Wash¬ 
ington, Philadelphia, New York, Cambridge and 
Chicago. Mr. Osgood divides the genus Pero- 
niyscus into six subgenera. His list of species 
and subspecies represents almost 160 different 
forms. The colored map showing the distribu¬ 
tion of these different forms is of the very 
highest interest. 
The work is highly creditable not only to the 
author of the paper, hut to the Biological Sur¬ 
vey. It is a good example of the practical use¬ 
ful service that the Biological Survey is con¬ 
stantly performing for the agricultural interests 
of the country, a service which should be far 
better understood than it is at present. 
The Most Destructive of Animals. 
The animal which is believed to work the 
most injury to man is the common rat. It 
annually destroys property worth many millions 
of dollars, and is the means through which the 
terrible disease known as the bubonic plague is 
disseminated. The infection is spread among 
the animals themselves, and from the rat to 
man by means of the flea which infests the rat. 
The Biological Survey of the Agricultural De¬ 
partment has given serious attention to the 
problem of how to put an end to, or at least 
minimize, the injury done by rats, ot which the 
most common and destructive is the so-called 
Norway or brown rat. This has been carried 
all ‘over the world, and wherever carried finds 
itself at home. In North America it occurs 
from the Isthmus of Panama to the Yukon 
Valley in Alaska and to Greenland. 
The rat eats almost everything, and many 
things that it does not eat it destroys. Grain of 
various sorts constitutes its favorite food, but 
it eats flesh, vegetables generally, and gnaws, de¬ 
stroys and pollutes a vast quantity of material 
which it does not eat. It kills poultry, steals 
eggs, destroys the nests of wild birds, and even 
sets fire to buildings by gnawing matches or 
the insulation of electric wires. 
The astonishing fecundity of the rat is a chief 
reason why man’s efforts toward its extermina¬ 
tion have proved futile. The female gives birth 
to large litters, and at frequent intervals. It 
has been calculated that a single pair of rats 
and their progeny, suffering no losses and 
breeding without interruption, would in three 
years increase to 20,000,000. 
The author of the Biological Survey Bulletin 
on the brown rat declares that hawks and owls 
destroy great numbers of rats, while weasels, 
minks and skunks are also effective enemies. 
Checks such as these, however, obviously can¬ 
not work in cities, where the depredations of 
the rat are greatest; but their useful work in 
the country should be encouraged. Traps and 
poisons are recommended as the best means of 
getting rid of rats, but better still would be a 
rat proof construction of buildings and the re¬ 
ducing the food supply of the rats by the dis¬ 
posal of garbage and the protecti’in of food 
supplies. On the other hand, instances have 
been known where rats in search of food have 
gnawed their way through from four to six 
inches of cement flooring. Broken glass mixed 
with the cement proves an effective barrier. 
The constant damage wrought by the rat is 
a waste that should be done away with. 
PURE MILK FOR BABY. 
Sanitary milk production was first started 
by Gail Borden in the early 50 s. The best 
systems to-day are largely based on his 
methods, but none are so thorough and so 
rigidly enforced as the Borden System. For 
over fifty years the Eagle Brand Condensed 
Milk h'as proved its claim as the best food for 
infanta.— Adv. 
