Proceedings of the Entomological Society of Washington
Only the elongated, more highly modified types of labium are discussed in the following brief notes, in which I have attempted to establish the homologies of the parts in higher insects; and the present brief discussion will serve as an introduction to a more, extensive paper which I have almost completed, dealing with the modifications of the labium throughout the orders of insects, from the standpoint of phylogeny. For the greater part of the material used in the preparation of the present paper, I am greatly indebted to the kindness of Drs. J. M. Aldrich, J. W. Campbell, C. W. Johnson, and A. L. Melander, and I would use this opportunity of expressing my deep appreciation of their generosity which has made this work possible.
Crampton, G. C., "A Comparison of the Labium in Certain Holometabolous Insects from the Standpoint of Phylogeny" (1923). Co. Paper 157.
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