382 Bulletin 148. 



have undoubtedly ruined many bushels of quinces, is a good illustra- 

 tion of the value of such experiments. 



The explanation of the appearance of the curculios during the last 

 week in July in 1897, and about May 26, or two months earlier, in 

 1896, is undoubtedly to be found in the difference in climatic condi- 

 tions of early spring in the two years. From the report of the New 

 York State Weather Bureau, we learn that " periods of abnormal 

 warmth obtained duiing April and May (1896), the maxima for the 

 former month being among the highest recorded for April." The 

 temperature conditions during a similar period in 1897 were nearly 

 normal. Our breeding experiments with the grubs in a warm office 

 and under normal out-door conditions, as detailed above, together 

 with the known climatic conditions just mentioned, seem to afford 

 conclusive evidence that the appearance of the curculios in the last 

 week in May, in 1896, was unusual, and abnormal for the latitude of 

 central New York, It is unfortunate that our observations on this 

 point do not extend over more than these two years, for it leaves it 

 still somewhat uncertain at what time in the spring the curcuhos 

 usually appear in New York. It is very doubtful if they often appear 

 as early as June i, and we believe that the last week in July is 

 unusually late ; probably their normal time for appearance is about 

 July 15, or possibly a little earlier in our state. Or the curculios 

 probably do not appear on the trees until the quinces are somewhat 

 larger than those shown in figure 191. 



Habits of the curculios or beetles. — For a week or more after they 

 emerge from the ground in the spring, the curculios feed upon the 

 growing quince fruits, and possibly to a shght extent upon the leaves. 

 The young fruits are covered with a thick fuzzy coating (in figure 191 

 a bit of this covering is loosened and turned back), but this offers little 

 or no protection against the attacks of the beetles. While they seem 

 to prefer to feed near the stem end of the fruit where the fuzzy coating 

 is thinner, still they are often seen feeding at other points. In feeding, 

 the curculio works its snout down through the fuzzy coating, eats a 

 hole about the size of a common pin through the skin of the fruit, 

 then proceeds to gouge out a pit or hole, often about the size of a 

 half pea, in the flesh just beneath the skin; its curved snout, with the 

 jaws at its end, is well adapted for this work. In figure 192, the skin 

 has been removed to show several of these holes made by the curculios 



