262 QUARTERLY JOURNAL. 



exhibits the shrivelled vestiges of some of the buds which have 

 failed to expand their leaves, and have withered in consequence of 

 all the juices destined for their growth having been absorbed by 

 the gall. These remains of buds form small holes, which commu- 

 nicate with the interior of the gall. The pup© pass the winter 

 season enveloped in cocoons within these galls, and when about 

 to change to their perfect or fly state, glide by little and little 

 along the channels produced by the perforations of the buds, to 

 their mouths, whence they emerge upon the wing. The extremi- 

 ties of other twigs of the willow, stung by another species of cecido- 

 myia, shoot forth a dense tuft of leaves, resembling a double rose 

 in their appearance, though retaining their green color, or like the 

 fruit of the hop. These singular appendages were very perplex- 

 ing to the earlier botanists, some of whom regarded the trees on 

 which they grew as distinct species from those on which they do 

 not happen to occur. Gerarde thus characterizes one of the English 

 willows as bearing something like roses, which make " a gallant 

 show — being set up in houses for the decking of the same, and 

 yielding a most cooling aire in the heat of summer." 



AMERICAN SPECIES. 



Hitherto but two species appear to have been noticed in this 

 country, to wit : the Hessian fly, scientifically named and descri- 

 bed by our accomplished and indefatigable naturalist, the late 

 Thomas Say — under which name, however, the recent inves- 

 tigations of Miss Morris seem to render it not improbable that 

 two distinct but closely related species may have been heretofore 

 confounded — and the wheat fly, probably identical with the C 

 tritici of Europe, but which has not as yet been so accurately 

 traced out and described in this country, as its importance de- 

 mands. But that there exist within our boundaries a number oi 

 other species, no one acquainted with our Entomology, an.l con- 

 sequently aware of the little attention that has been as yet be- 

 stowed upon our Dipterous insects, will doubt. Their minute 

 size, the short period of their existence after attaining their per- 

 fect state, the obscurity of their retreats, and their seldom being 

 much upon the wing during the day time, are circumstances that 

 have enabled them to elude the researches of those few individu- 



