168 Annals Entomological Society of America [Vol. XV, 



SHAPE OF THE HEAD CAPSULES. 



There are certain differences in the shape of the head capsules 

 that help to distinguish some of the instars. The head capsule 

 of the first instar is distinctly flattened while the capsules of 

 the remaining instars are rounded and easily separated. A 

 comparison of the heads further show that those of the first 

 seven instars are proportionally longer than broad, while the 

 eighth, ninth and tenth larval heads are proportionally broader 

 than long. These differences in shape, as well as the differences 

 in size, aid in determining the different instars. 



REFERENCES. 

 *. Slingerland, M. V. The Bud-moth, Cornell Bull. 50, pp. 1-29, 1893. 

 f. Sanders, G. E. and Dustan, A. G. The Apple Bud-moths and their Control 

 in Nova Scotia, Dom. Canada Dept. Agric. Bull. 16, 1919. 



