"A. N.," Chicago, Ill., writes: "In this State, pear blight has always been very destructive. There are some old trees, but millions have been swept away, where these have grown.

" Perhaps after we know the cause, we may not get the remedy. But we do not know that we will not, therefore we desire to learn the cause whatever it be. For my part, I have been inclined, of late, to the bacterial theory, and yet there are some considerations that make me hesitate. In one of your letters you told me, that the fire blight is almost unknown in Germantown. But I suppose the microscope could show myriads of bacteria. Why don't these creatures plague you as they plague an Illinoisian? Do they hesitate totackle the Editor of the Gardeners' Monthly? And England swarms with bacteria, if we may credit the scientific journals. Why don't they bother the English pear-grower? I believe nothing of the kind was ever heard of there." To all of which we can only say, that if it can be proved that bacteria do cause the disease, it is no argument that they do not cause the disease, because it is not seen in England. Still the freedom of England under the circumstances, would be remarkable.

Prof. Burrill, decides that the Bacterian found in connection with pear blight is no ordinary fellow, but a species hitherto undescribed. He names it Micrococcus amyvorus, as we see quoted in an exchange, though we have not his original description to hand.