334? On Blight. 



gain the confidence due to them. I did not dare to give an 

 easy receipt for the cure of tlie dry rot, till it was proved to be 

 a good one by Lord Heathfield, who found it succeed. I 

 now may, therefore, venture to give my opinion. By my 

 advice, Lord Heathfield caused proper passages for the ad- 

 mission of common dry air, which became an effectual cure ; 

 and I persist in it, that, where there is a certain proportion of 

 dry air, these fungi are not to be found, but only in those 

 seasons when such is natural to the climate. They indicate 

 a certain temperature, like a thermometer, pointing it out 

 when we otherwise do not perceive it; and we may be assured 

 that a certain degree of moisture and temperature is as 

 necessary for the growth of the fungus tribe as any other." 

 These remarks, although they do not supply a definite 

 prescription, may not be wholly useless. Mr. Sowerby was 

 furnished with specimens on June 17. 1807, by John Walker, 

 Esq., of " some wall trees, at his seat at Southgate ; it 

 covered, nearly in this manner, a large number of trees. Mr. 



Walker had the leaves stripped from the trees 



On October 12. 1807, William Lewis, Esq., sent me, from 

 Hendon, the leaves of a Chaumontelle pear tree, which grew 

 against an open fence, the inclination of which was to the 

 south-east." 



Mr. Merrick will find farther notices on this subject, in 

 p. 329. 332. of the present Number: Mr. Knight's mode of 

 preventing the effects of the ^cidium cancellatum will be 

 impracticable in the case of trees so old and large as those 

 under the care of Mr. Merrick. 



In further connection with the preceding mention of 

 blights by fungus, we shall here introduce to the con- 

 sideration and canvassing of our practical friends some 

 notices on blights produced on plants by insects : they are 

 written by Rusticus of Godalming, a valued contributor to 

 our Magazine of Natural History ; but are published in the 

 Entomological Magazine^ an excellent quarterly journal, price 

 3s. 6d. a number, devoted solely to information on insects. 

 We feel no apprehension of the proprietors of that work being 

 at all displeased at the liberty we are taking, as we know 

 their foremost wish is to diffuse entomological knowledge. 



" Observations on the Blights of the Apple" Tree, and its 

 Fruit. — "I don't know why our brethren on the other side 

 the Atlantic are charged with sending us the greatest pest of 

 our orchards ; but so it is. We call an insect the American 

 blight, which, for aught I could ever make out, may have come 

 from China or Botany Bay. However, a name once in vogue 

 will have its day ; and one might as well attempt to turn a pig 

 ' in an entry as argue against an established belief; so American 



