1847.] Winter Insects of Eastern New York. 11 
may therefore prove to be identical with the P. humicola of Otho 
Fabricius (Fauna Gréenlandica,) of which we are unable to refer 
to any but short and unsatisfactory descriptions, which do not co- 
incide well with our insect. 
This is an abundant species in our forests in the winter and fore 
part of spring. At any time in the winter, whenever a few days 
of mild weather occur, the surface of the snow, often, over whole 
acres of woodland, may be found sprinkled more or less thickly 
with these minute fleas, looking, at first sight, as though gunpow- 
der had been there scattered. Hollows and holes in the snow, out 
of which the insects are unable to throw themselves readily, are of- 
ten black with the multitudes which here become imprisoned. 
The fine meal-like powder with which their bodies are coated, 
enables them to float buoyantly upon the surface of water, without 
becoming wet. When the snow is melting so as to produce small 
rivulets coursing along the tracks of the lumberman’s sleigh, these 
snow-fleas are often observed, floating passively in its current, in 
such numbers as to form continuous strings; whilst the eddies and 
still pools gather them in such myriads as to wholly hide the ele- 
ment beneath them. 
