240 



THE AMEEICAN ENTOMOLOGIST. 



portnnity of making observations that may 

 throw some light upon both these questions. 



The females began to deposit their eggs to- 

 wards the latter part of April, some two weeks 

 later than usual in this latitude, the season be- 

 ing backward and unusually cold; and about 

 the first of June the full-fed larvre were ob- 

 served to be leaving the fallen fruit and going 

 into the ground. By this time, the Curculio 

 Catcher having been kept running every day 

 when the weather would permit, there was a 

 very marked diminution in the numbers of the 

 insects, and very soon after there were very few 

 to be found. But about the last week in June 

 there was a sudden and large increase in the 

 numbers caught, and the supply was well kept 

 up until -within two weeks past when they 

 seemed to be again pretty nearly caught out. 

 That this fresh supply was composed of young 

 Curoulios, the product of the eggs deposited in 

 April and June, and not of old ones or immi- 

 grants from other orchards, is proven, if proof 

 were needed, by the suddenness of the increase, 

 by the fact that many of them were found copu- 

 lating, and by the further fact that most of them 

 were so soft from their recent emergence from 

 the earth as to be readily crushed between the 

 thumb and finger. Finding many of them in 

 the act of pairing, as I often found them in their 

 first appearance in the spring, I supposed them 

 to be preparing for the production of another 

 generation the present year. But the closest ob- 

 servation has not enabled me to find a single in- 

 stance of their depositing an egg. I cannot find, 

 on peach or plum, a single recent crescent- 

 shaped cut. To satisfy myself more fully, I im- 

 prisoned about fifty of them in a box with a 

 glass cover, and gave them a daily supply of 

 green plums and peaches ; but, though they fed 

 voraciously upon the fruit, not a single egg was 

 deposited. Hence, I conclude that the Curculio 

 does not, usually at least, produce more than 

 one brood in the same year. 



With regard to the second question. I pre- 

 sume that all who are at all familiar with the 

 habits of the Curculio know that it feeds upon 

 the fruit, preferring that which is approaching 

 maturity. Very few know, however, how rav- 

 enous its appetite is. The peaches and plums 

 given to those I had imprisoned, were literally 

 peppered all over with holes, some no larger than 

 a small pin's head, and some large enough for 

 the insect to bury itself bodily in the flesh of 

 the fruit. Even a handful of peach leaves 

 " thrown in with the fruit, were perforated in a 

 hundred places. Now, that a wound in the 

 skin of a peach just swelling to maturity with 



its abundant juices, should produce rot, is in 

 accordance with both reason and observation. 

 In every instance where I could detect the I'ot 

 in its incipient stages, and before the surface 

 had become so much disorganized as to destroy 

 all trace of it, I could distinctly see the abrasion 

 of the skiu from which, as a center, the decay 

 had proceeded. I caught a Curculio feeding 

 upon a peach. It had made a hole half as large 

 as a grain of wheat. I marked the place, and 

 in a few days found a rotten spot with the hole 

 in the centre. 



Let me give you further proof. I have five 

 trees of the Hale's Early peach which have pro- 

 duced two crops of fruit before the present 

 year, not a single specimen of which ever 

 ripened. They rotted before maturity to the 

 last peach. This season, one of the very worst 

 for rot that I have ever known, these trees have 

 ripened a full crop of sound fruit. I kept the 

 Curculio caught oft" them as completely as was 

 possible, and pulled oft' all decaying fruit as 

 soon as it made its appearance. Those fruits that 

 were eaten into rotted, the rest remained sound. 



I have several other trees of the same variety 

 in another orchard that were well loaded with 

 fruit. These were neglected, except that they 

 were well cultivated. The result was that not 

 a single peach ripened. My neighbors who 

 failed to fight the Curculio but trusted to luck, 

 lost their crops of this variety entirely, or saved 

 them in part onlv by gathering the fruit so 

 green that it was more fit for grapeshot than 

 human food. At South Pass, as I am informed, 

 those only who persistently caught the Curcu- 

 lio had an)' decent Hale's Early peaches. 



I do not wish to be understood as maintain- 

 ing that a peach never rots unless the skin is 

 first broken. On the contrary, I believe that, if 

 the decaying fruit is permitted to hang upon 

 the tree or to lie festering in the damp weeds 

 and grass on the ground beneath, it will breed 

 a pestilence that even the soundest fruit may 

 not resist. Every decaying peach is covered by 

 a forest of fungi, each one of which, in a single 

 day, perhaps, ripens and scatters its myriads of 

 invisible sporules. These, in their turn, vege- 

 tate and produce other foi'ests, and so the rapid 

 reproduction proceeds until the orchard is foul 

 with the seeds of a disease, whose contagion 

 none but the hardiest fruits can escape. 



It seems to me clear, therefore, that the rot of 

 peaches and plums is caused, in most cases at 

 least, by the punctures in the skin of the fruit 

 made by the Curculio in taking its food, and 

 that this mischief is done by the young brood, 

 the old ones having perished. 



