THE BIOLOGICAL REVIEW. 75. 



The galls are usually found on plants growing in the shade of 

 open woods. 



I am indebted to Prof. Riley, of Washington, for a satis- 

 factory identification of this gall. 



MELCE AMERICANUS. 



In Vol. 9, page n, of the Canadian Entomologist are notes, 

 by me on M. angusticollis, and on page 75 there is a compre- 

 hensive article on the distribution of the genus, and some 

 remarks on my notes, by Mr. Caulfield, of Montreal. 



At the time these notes were published I was under the 

 impression that the fall and spring forms were of the same 

 species : the form americanus always found in the fall season, 

 the form angusticollis always in the spring ; and that the small 

 difference between the two was caused by the pupa or semi- 

 pupa being accidentally retarded in development, and thus 

 passing the winter in the immature form. Perhaps the remark- 

 able scarcity of the spring form, angusticollis, in Ontario 

 suggested this idea. Anyway, my published notes were alto- 

 gether on the fall form, which I presume is, without any doubt,. 

 M. americanus Leach. 



After the appearance of Mr. Caulfield's article I began a 

 series of experiments, with the view of producing, if possible,, 

 the spring form, M. angusticollis, from larvae and pupae of the 

 fall form, by retarding development with cold artificially 

 applied. I failed in pushing this attempt to a satisfactory con- 

 clusion, and, as it is not likely that I will ever again resume the 

 inquest, I submit a few notes made at the time, which may yet 

 be of some value, though too long delayed. 



On September 29, 1878, I captured two pairs of M, ameri- 

 canus while feeding on R. acris. I put them in a large earthen- 

 ware cage, sodded to a depth of several inches, and fed them 

 with the leaves of several species of Ranunculus, of which they 

 partook freely, but seemed to prefer R. acris. They nibbled at 

 potato tops and raw potatoes, but refused to taste tomatoes, 

 both leaves and fruit. 



