An article in the last Horticulturist, by "Terra," somewhat timidly suggests the probability of the disease known as "Leaf blight and cracking of the Pear," being caused by a fungus somewhat similar to the vine-mildew, or Oidium. The writer need not be the least timid, even though his idea should conflict with the theories of our ablest American Pomologists, which I admit it does. Not one of them can offer anything more plausible or as much so, as this, for which there is the highest European authority, that of " M. J. B." of the London Gardeners' Chronicle, also the most eminent Continental cryptogamic botanists. With such opinions on his side, he can readily dispense with the confirmations of merely practical fruit growers, whose opportunities and pursuits shut them out from the difficult and obscure field of microscopic botany. Let no sneers deter the earnest and humble inquirer from his purpose. The intelligence and powers of reasoning with which man has been endowed, urge him to persevere until the hidden and marvellous phenomena of nature hitherto unapproached by the naturalist shall be clearly defined.

Man's manifest destiny and progressive spirit demand that he shall declare the truths of science in the face of all human ignorance and opposition.

This, very reasonable cause has been laughed at by many known writers in this .country, but this will not render it any the less true or plausible.