102 



Bulletin 187. 



In some localities the foliage on many apple trees was badly dam- 

 aofed by the palmer-worms, but many reported much damage to the 

 young fruits also. This peculiar habit of eating the fruits is not 

 mentioned in the accounts of the outbreak of the insect in 1791, but 

 in 1853 much fruit was ruined by the caterpillars. In 1900, while 

 they destroyed many thousands of young apples in some orchards, 

 the trees were usually overloaded, so the loss was not so noticeable. 

 Their manner of working on the fruit is graphically shown in hgure 

 29. where two of the caterpillars can be seen at their nefarious 



28. — Ajiple leaves shietonized hy palmei'-icorms, natural size ; also young 

 leaves at tip of hranch badly eaten, near center at top of figure, 

 reduced. 



V 



work. Irregular holes, sometimes extending into the core, and of 

 varying sizes and depths are eaten into the sides of the fruits ; some- 

 times a long, irregular, shallow furrow will be eaten nearly around 

 the fruit. Usually the caterpillar spins more or less silk across the 

 cavity, as is shown in fi<>'ure 29. Where the hole extends to the 

 core, the fruit often withers and drops off, while many slightly 

 injured fruits remain and ])artly overgrow the injury, l)ut never 

 make first-class fruits. This fruit-eating habit of the caterpillar 

 makes the insect a much more destructive and serious pest than it 



