208 Forest Trees of Massachusetts. [April, 



history must apply to that species which has so frequently been 

 observed to deposit its eggs on the leaf." 



I have referred above to the drawings of Le Sueur, which con- 

 firmed my opinion that the insect I was observing, is Say's Ceci- 

 domyia destructoi-. On comparing these drawings with those of 

 Dr. Fitch, which he speaks of as being accurately correct, (which 

 I do not question,) I find so marked a difference, that I am certain 

 I should not have been misled by them. 



1 do not presume to decide; but there appears to my unlearned 

 eye a sufficiently marked difference from which to describe a 

 species. It would be impossible for me to give an idea of the 

 number of specimens that, in the summer of 1841, I examined 

 through a microscope, with Le Sueur's drawings by ray side. 

 Suffice it to say, I did little else for two months; and so perfectly 

 identical did these specimens appear with the drawings, that after 

 each examination I rose W'ith renewed admiration for the genius 

 of the distinguished artist. 



I have now before me files of pamphlets and newspapers pub- 

 lished since 1840, denying the truth of the theory advocated by 

 me. In some it is asserted that I have mistaken a weevil or a 

 curculio for the Hessian fly; in others, that I have been watching 

 the Cecidorayiatritici; while a third declares it to be a Bombyx; 

 and a fourth, that I know nothing about the matter. To all this 

 I have become accustomed; but I must confess that, after all the 

 evidence I gave in the shape of actual specimens, deposited in so 

 public a place as the Academy of Natural Sciences in Philadel- 

 phia, I feel some surprise at being expected to confess myself in 

 error, before I have equally strong evidence that I am so. 



M. H. MORRIS. 



Germantoinu March Sth, 1847. 



FOREST TREES OF MASSACHUSETTS. 



Report on the Trees and Shrxtbs groiving naturally in the Forests 

 of Massachusetts. Published, agreeably to an order of the 

 Legislature, by the Commissioners on the Zoological and Bo- 

 tanical Survey of the State. Boston : Button Sf Wentworth, 

 State Printers, Mo. 37 Congress street ; 1846, pp. 547, Svo. 



This report is from Mr. Geo. B. Emerson, Chairman of the 

 Zoological and Botanical Commissioners, appointed under the 

 law authorizing the Geological Survey of Massachusetts. It is 

 the concluding work of the survey; and as a result, it is what the 

 public expected — an interesting and valuable work, the merits of 



