32 YALE AGRICULTURAL LECTURES. 



abroad the last of March, if the weather is fine, though usu 

 ally it is not till about the middle of May ; and in a week or 

 two after it becomes quite common. It is found standing or 

 slowly walking upon the trunk and limbs of the plum, cherry, 

 apple, the wild thorn-apple, the butternut, and other trees. 

 Those on the butternut are plumper than the others. From 

 this time onward, till cold weather returns, we continue to 

 meet with it, and late in autumn it is to be seen on the flowers 

 of the golden-rod as plentifully as at any time through the 

 season. When the young fruit appears, in June, it attacks it 

 with the skill of an epicure, selecting the choicest varieties 

 first. Its crescent-shaped incision is the signal of destruc 

 tion, as was the crescent banner of the Moslem of old. The 

 slit made,one egg is deposited ; and but one slit is made on a 

 fruit. The peach, plum, and apple, when stung, wilt and fall; 

 but the cherry and thorn-apple do not. This is because the 

 larger fruit contains a sufficient amount of nourishment to ma 

 ture the worm ; while the smaller ones must grow on to elab 

 orate the quantity of food which the worm needs. It is a fact 

 not generally known, that apples are attacked by the plum cur- 

 culio, yet so great are the losses of this particular fruit, that the 

 lecturer gave it as his opinion that the poorer yield of our or 

 chards now, as compared with heretofore, is due to this insect. 

 The wilted fruit literally covers the ground, under many trees, 

 the fore part of July. Cut into this fruit and you will find the 

 same curculio worm therein as in the fallen plums. 



From the fact that this insect comes forth three weeks be 

 fore there is any fruit ready for it to eat, and remains after the 

 fruit is gone, Dr, Fitch thinks that it has other places of refuge 

 to cradle its young besides the young fruit. In fact, it is well 

 ascertained that it breeds in the black knot excrescences on 

 plum and cherry-trees, as eagerly as in young fruit. Hence it 

 has been thought to cause the excrescences. But having exam 

 ined the black knots fully in every stage of their growth, Dr. 

 Fitch says decidedly they are not produced by this or any 



