Slimmer. They remain with their mother until old enough to shoul- 
der their own responsibilities. For several weeks after birth their 
color is tawny yellow, quite different from the shining olive brown 
of the adult- The babies never know a nest or home of any sort. 
During the day they cling and nurse, closely wrapped in the elastic 
folds of the maternal wing membranes, but "when the old bat flits 
off into the twilight the youngsters often go with her, clinging about 
her neck, swinging away over the tree-tops and along the foggy 
water-side, while she chases the numberless little flying things of 
the dark. 
"At times, however, she deposits them on the branch of a tree, 
where they hang sheltered by the leaves, while she goes off foraging 
l)y herself."* 
2. SILVER-HAIREEl BAT 
Lasionycteris noctivagans (Le Conte) 
Length 10 centimeters (4 inches). Teeth: incisors ^l, canines ^Ej, premolars 
"_,. molars jE;, =36. Color black. The fur narrowly tipped with silver\- white. 
Ihe basal portion only of the upper surface of the interfemoral membrane with fur. 
i:ar short and broad. 
The Silver-haired Bat, though rare on Long Island during most 
of the summer, is "tolerably common"t in Westchester County and 
the upper Hudson Valley, while in the Adirondacks, according to Dr- 
C. Hart Merriam, it is the "commonest bat, far outnumbering all 
the other species together." Of its status here Mr. Arthur H. Helme, 
in his "Notes on the ^lammals of Long Island," writes: "Some years 
it is very plentiful, especially in late summer and early autumn, 
outnumbering even the Red Bat." We have, then, good evidence of 
a southerly migration of this species as the winter season approaches. 
And yet by no means do all the Silver-haired Bats depart before 
the snows. Perhaps an extraordinarily deep cavity in a tree trunk, or 
a quiet dark house-loft oft'ers tempting inducements for winter camps. 
At any rate Silver-hairs, compacted into furry little oblongs and 
utterly oblivious to the world around them, are not infrequently found 
in hollow trees cut in winter for firewood, and they also have been 
discovered hibernating in sky-scrapers, churches, wharf-houses, and 
the hulls of ships in New York City and Brooklyn, during the 
*Stonc & Cram. .American .Animals, 1902. 
tjohn Rowley. The Mammals of Westchester Count\-. New York. 1902 
