60 
ORDERS OF MAMMALS— BATS 
From the bats of the United States, there is 
nothing to fear, for their claws and teeth are 
pitifully weak. One cross old “bumble-bee,” 
angrily bumbling, is more dangerous to a peace- 
ful community than all the bats of our country 
taken together. In some portions of South 
America, however, the vampire bats cause seri- 
ous trouble. 
Keen-eyed boys and girls all over the world 
should know that little is known concerning 
SKELETON OF PALE BAT. 
Antrozous pallidus. 
the habits of bats, and much remains to be found 
out. These creatures are therefore excellent 
subjects for original investigation. 
The Order of Bats as a whole contains about 
four hundred and fifty species, but it is safe to 
say that three-fourths of them are known only 
by their dry skins and skulls, and that their 
habits are quite unknown. The questions are, — 
why do bats live? Upon what do they feed? 
Are they useful to man, or injurious? What 
are their friends and their enemies? Do they 
migrate, and at what times? Where do they 
nest, or take shelter; and what are the facts 
about their young? What parasites and dis- 
eases have they? 
Although the bat is a true mammal, it is al- 
most as wide a departure from the ordinary, 
four-legged, land-going type as is a whale or 
manatee. Its hand reveals an extreme degree 
of what is called “specialization.” For a mam- 
mal, the arms are of great length. The bones of 
the fingers are enormously extended, and con- 
nected with hairless skin as flexible as india 
rubber, to form a wing for flight. This Aving 
membrane is extended on up the arm to the 
body and the legs, and is continued between 
the legs and tail, Avhere it forms a supporting 
parachute in flight. 
The thumb of a bat is very short and free; 
and its nail is developed as a hooked claAV, by the 
aid of which the creature can comfortably climb 
about or support itself. The favorite position 
of a bat at rest is hanging by its feet, head down- 
ward. 
To be “as blind as a bat” is not to be blind 
at all, but rather to possess powers of \dsion that 
are uncommonly good in semi-darkness, or at 
night, and fairly good even in the broad light 
of day. When disturbed at midday, all the 
bats I have ever seen alive (perhaps twenty 
species in all) have flown away to places of se- 
curity as briskly and successfully as so many 
swallows. The eyes of all night-flying bats are 
small, jet black, and look like tiny black beads, 
but those of the day-flying fruit-bats are very 
much larger in proportion. 
The teeth of bats of different species show 
wide variation. In nearly all of the four hun- 
dred and fifty species, the canine teeth are as 
strongly developed as in the cat, and in some 
bats their proportions are really formidable. 
A careless examination of a bat’s skull might 
easily lead one to believe that it belonged to a 
earnWorous animal. But the molar teeth will 
always tell the true story. 
The insect-eating bats, which far outnumber 
all others, have cheek-teeth which terminate in 
sharp points, and are specially designed for cut- 
ting to pieces the hard parts of hard-shelled in- 
sects. The fruit-bats, however, have molars 
of a very different sort, with rather smooth 
crowns, for crushing instead of cutting. The 
blood-sucking vampire bats of South America 
have very large canine teeth with sharp, cutting 
edges, and even the molar teeth are formed with 
scissor edges, very much like the teeth of cats. 
The teeth and skulls of bats exhibit many in- 
teresting and even extraordinary variations, 
but it is impossible to enumerate them here. 
The accompanying figures show the characters 
of two species found in the United States. 
As previously remarked, very little is known 
regarding the habits of bats, chiefly because 
their nocturnal habits make it A^ery difficult to 
find them, or to observe them. We know that 
in winter some of our species live in ea\ r es, in a 
semi-dormant condition. Dr. C. H. Eigenmann 
