1847.] JVoxious Insects. 151 



account, inferred to be the Thrips cerealium, (Treatise, p. 444). 

 The species would seem to be scarcely different from the Europe- 

 an P. bipimdatus, except that the stigma has no black spot. It 

 may be named and characterized as follows: 



Psocus tritici. Dark-brown or black, shining; wings hyaline, 

 upper pair with a black dot on the middle of the anterior and 

 another on the middle of the posterior margin ; abdomen dull 

 pale-yellow, commonly annulated with black. Wings ex- 

 pand 0.10. Variety a. Abdomen white, without bands, 

 with a fulvous dorsal line. 



In Forests, on the Surface of Melting Snow, Buckets of Maple 



Sap, and Pools of Water. 



A minute, dull, blue-hlack flea. 



The Snow Flea. 



This is an abundant species in our forests in the winter and 

 fore part of spring, breeding, it is supposed, at the very period 

 when nearly all the rest of the animal and vegetable creation is 

 reposing in torpidity, under the influence of hyemal frosts and 

 snows. It probably subsists upon decaying vegetable substances. 

 When ever a few days of mild weather occur at any time in the 

 winter, the surface of the snow, often, over whole acres of wood- 

 land, may be found sprinkled more or less thickly with these 

 minute fleas, looking, at first sight, as though gun-powder had 

 been there scattered. They advance with slight leaps, which are 

 produced by means of their tails. This member is forked at its 

 tip, is flexible and elastic, and lodged, when at rest, in a groove 

 under the abdomen. The tail moves as if with a spring, and 

 striking the surface on which the insect is placed, throws it a 

 short distance. It commonly falls upon its back with the tail 

 extended. Hollows and holes in the snow, out of which the in- 

 sects are unable to throw themselves readily, are often black with 

 the multitudes which here become imprisoned. Their bodies are 

 coated with a fine meal-like powder, of a blue-black color, analo- 

 gous to that on the surface of cabbage leaves; this 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 element 

 beneath them. In the early spring, the buckets and troughs em- 

 ployed to receive the sap from the maple tree, are often similarly 

 thronged with them; rendering it necessary to carefully skim or 



