THE MUSEUM 
OF 
THE BROOKLYN INSTITUTE OF ARTS AND SCIENCES 
SCIENCE BULLETIN 
VOL. 2, NO. I. 
LONG ISLAND FAUNA AND FLORA— L 
THE BATS (Order CHIROPTERA). 
By Robert Cushman Murphy and John Treadwell Nichols. 
Bats have their closest affinities with the Insectivores ; but they 
are more sharply marked off from their nearest relatives than any 
other mammalian order. 
Among the specialized structures correlated with their habit 
of aerial locomotion are the extensible membrane stretching from 
the sides of the body, connecting the greatly elongated digits 
of the hand, and extending from thence to the hind Hmb and usually 
to the tail ; and the rotation of the axis of the femur so that the knee 
projects outward instead of forward. These characters, which make 
possible exceedingly dexterous and graceful flight, render bats awk- 
ward and all but helpless on a flat surface. 
The mammae are pectoral, and there is commonly but a single 
pair. Tactile organs of astonishing delicacy are present in the skin 
of the wing membranes, and there are not infrequently other struc- 
tures of sensory importance, such as leaf-like appendages on the 
snout, and the elongated tragus of the ear. Extended experiments 
have shown, however, that neither the ear pinna nor the tragus are 
necessary for the perception of obstacles while the bat is in flight. 
Perception is probably due to the condensation of the atmosphere 
between the bat and the object it is approaching, and the sense organs 
involved are located inside the ear. 
There is much evidence to show that a sense of direction exists 
in bats.* 
Among most bats the type of reproduction is unique. Copulation 
occurs in autumn before hibernation begins. At this period some 
agency, probably an exudation from the preputial glands of the 
*W. L. Hahn, Some habits and sensory adaptations of cave inhabiting bats, 19()S. 
