18 



February 19, 1852. 



Evening Meeting. The President, Hon. D. A. White, in 

 the chair. 



Dr. Henry Wheatland presented a view of the Mollus- 

 cous Animals, which are found on our coast, their ar- 

 rangement in conformity to their zoological development 

 and geological groupings. 



The Canker on the fruit of the Pear came up for 

 discussion. Mr. R. Manning supposed the injury to the 

 fruit to originate from the presence of some sort of fungus, 

 which hardening the skin of the immature fruit, or 

 partially depriving it of vigorous vitality, causes the 

 cracking and thereby it does not properly ripen. He was 

 inclined to consider the black spotting on the leaves to be 

 identical with the first perceived infection of the fruit. 

 The bitterness attendant on the canker or cracking of the 

 fruit seemed not as yet explained : neither was the cause 

 of the fungus blight easily, if at all, settled. He was not 

 fully able to say what the soil had to do with the matter. 

 Many quite newly introduced varieties of the pear showed 

 a decided tendency to this disease. In some seasons, there 

 was a remarkable freedom from any sort of taint on all 

 the varieties; a peculiar fact certainly. 



Mr. Russell was of the opinion that soil had little to do 

 with the matter. In some situations, as for instance in the 

 gardens of Boston, within a few years of his own knowl- 

 edge, the St. Michael and Brown Beurre were produced in 

 perfection. On the Connecticut River the St. Michael was 

 still free from canker. Yet at Brattleboro', Vt., where this 

 old and esteemed variety is cultivated with success, he 

 noticed the black spotting on the leaves. If this should 

 prove to be a fungus, it would seem to foretell the final 

 issue of the fruit. But a stricter attention to the character 

 and nature of these minute and insidious parasitic plants 

 Mr. R. recommended to horticulturists, by which their 

 presence or action on the subjects of their care could be 

 certainly ascertained. 



Mr. J. Fisk Allen confirmed Mr. Russell's statements 

 relative to the ^S*^. Michael pear from the older Boston 

 gardens. He considered the question of soils an obscure 

 one as relative to the complaint. He assented to Mr. 

 Manning's rationale respecting the fungus cause of Canker; 



