56 
Psyche 
[June 
broken when the inner end of the stomodseum pushes 
through. The peritrophic membrane, as described by Wig- 
glesworth, is chitinous and arises from a mass of cells cor- 
responding in position to the base of the stomodseum in the 
embryo. This indicates that the peritrophic membrane is 
ectodermal in origin. 
Literature Cited 
Campbell, F. L. 1929. The detection and estimation of in- 
sect chitin; and the irrelation of chitinization to hard- 
ness and pigmentation of the cuticula of the American 
cockroach, Periplaneta americana L., Ann. Ent. Soc. 
Am., Vol. 22, pp. 401-426. 
Nelson, J. A. 1915. The embryology of the honey-bee, 
Princeton University Press, pp. 1-282. 
Snodgrass, R. E. 1925. Anatomy and physiology of the 
honey-bee. McGraw Hill Book Co., New York, pp. 
1-327. 
Wigglesworth, V. B. 1930. The information of the peritro- 
phic membrane in insects with special reference to the 
larvae of mosquitoes. Quart. Jour. Mire. Sc., Vol. 
73, Part IV, pp. 593-616. 
