38 V THE CANADIAN ENT0M0L(J(I1ST. 



worst, I have not seen a score of them all through the summer. 1 noticed 

 one or two on my own trees showing the crescent cut, l)ut no more. It 

 was almost as safe to eat the fruit unexamined, as it is in England. 



By the way, I never hear any apprehension expressed concerning the 

 migration of Conotrachelus nenuphar across the Atlantic. Though fruit 

 is less abundant there than here, yet the introduction of this pest would be 

 a very serious drawback to the enjoyment of plums, jjeaches and cherries, 

 not to mention the loss caused by its attacks on the apple. 



On the other hand, if these insects are less injurious in Pennsylvania 

 than in Ohio, the imported curr^fnt worm is more so, and the growth of 

 currants is greatly limited by its ravages. \'ery iaw persons seem to 

 know what can be done by the use of poison to rescue the bushes and the 

 currants. Great, but totally unfounded prejudice also e.xists against the 

 use of poison, even on potatoes : many people seeming to fear lest the 

 potato should absorb sufficient arsenic to render its use as a table vege- 

 table dangerous. It is needless to say that all such ground of alarm has 

 long been set at rest in the minds of those who have followed the jjrogress of 

 economic entomology. But prejudice is blind to reason aiid slow to die away. 



In addition to this the various web-worms on the forest trees are vastly 

 more numerous here than they were at Yellow Springs. In earliest spring 

 and before the leaves are generally out, the American Lackey Moth ( C. 

 Americana) lakes possession of tlie cherry trees and covers the young 

 foliage with its net. Soon afterwards the Forest Lackey ( C. sylvatica) 

 follows on the same tree, but more frequently on the apple, and later still the 

 walnuts are attacked by the Fall web worm ( H. textor), whose nests remain- 

 ing on the trees after the fall of the leaf, disfigure them through the winter. 



This year, also, the oak caterpillar (D. senaforia) ha.'^ wrought great 

 ravages in the forest. 1 have seen hillsides that looked as if fire had 

 passed over them in consequence of the destruction of the foliage by 

 millions of this species. In the woods they could be tbund crawling over 

 almost every square foot of ground and lying dead l)y dozens in every 

 pool of water. The sound of their falling frass, too, was like a slight 

 shower of rain. Farmers tell me they have never known them so abun- 

 dant before within their recollection. Harris says this species lives on the 

 White and Red Oaks ( Q. alba and rubra )'\Xi Massachusetts. Here the 

 White Oaks were untouched, and the Red Oak is not abundant. The 

 food of the caterpillars was almost exclusively the foliage of the Black Oak 

 (Q. tinctoria ), the Scarlet Oak ( Q. coceinea), and the Bear or Scrub Oak 

 (Q. ilicifolia.) 



