INSECTS INJURIOUS TO ORCHARD FRUITS 



501 



nearly one-third inch long, light brown in color, somewhat pitted, 

 and the male pupa bears a simple spine at the tip of the abdomen. 



The Fall Canker Worm * 



The Fall Canker Worm seems to be the more common form in 

 New England according to Dr. Britton and is a more northern 

 species according to Coquillet, occurring through the North- 

 Central States and in Colorado and northern California. As its 

 name indicates, it differs in life history in that the moths emerge 

 in November and December, " of ten occurring in great numbers 

 on foggy days during a thaw after the ground has been frozen." 

 They are most numerous about the middle of November in Con- 

 necticut, although Dr. Britton states that when the ground freezes 

 in early fall and does not thaw, 

 many of the adults do not 

 emerge until March, when the 

 life history would be identical 

 with the last species. The eggs 

 are laid in clusters of about 

 100, arranged in rows, each egg 

 fastened on end, and are laid 



^ 



and dorsal views of larval segment 

 enlarged; e, egg mass; /, larva; a, fe- 

 ma l e pupa-natural size; fc, anal tub- 

 ercle enlarged. (From Riley.) 



onthebarkofthesmaHerbran- 



ches or on the trunk. The 



i i 



egg is brownish-gray, rather 



darker than that of the spring 

 species, and is shaped like a flower-pot, the outer end being marked 

 with a dark spot in the centre and a dark ring near the margin. 

 The eggs hatch in late April and early May in Connecticut. The 

 larvae are very similar in general appearance to those of the spring 

 canker worm, but may be easily distinguished by having two 

 pairs of prolegs on the middle of the abdomen. The pupa is sim- 

 ilar to that of the other species, but is somewhat stouter and the 

 spine at the tip of the abdomen of the male pupa is always forked. 

 The cocoon is much tougher, contains more silk, and is therefore 

 less easily crushed. The male moth is slightly larger than that of 

 the other species, with longer antennae, and the wings are firmer, 

 less transparent and darker in color. The fore-wings are crossed 

 by two whitish bands, the outer one being indented on the front 

 * Alsophila pometaria Harris. Family Geometridce. 



