A GENEALOGIC STUDY OF DRAGON-FLY WING VENATION. By James G. Needham, Of Lake Forest College, Lake Forest, lllmois. INTR0DU(1TI()N. This is a new study of one of the oldest subjects in entomology. It \s an application of' the n.ethods of comparative morphology to the interpretation of some external characters universally employed in 3y8tematic work upon insects. I The richly veined wings of dragon-flies have been carefully studied i)y many able entomologists; their interesting peculiarities are well known -/the homologies of the various parts of the wing have been determined throughout the order; and there already exists a consider-able body of evidence as to the nature and extent of variation in Jvenational characters. There has been as yet no serious effort to use khese characters to determine genealogic succession within the order Sit is the main purpose of this paper to translate the records of natural I selection as written in the al)undant characters of these wings.. At the outset I wish to acknowledge ipy indebtedness to the f ollow-! ino-oentlemen, who have all aided me generously: To Prof. J. H. Com-' stock, of Cornell Universitv, I am indebted first of all for constant I advice throughout the progress of this study; to Mr. Samu(4 Henshaw, ' of the IVIuseum of Comparative Zoology, for free use of the llagen Collection of Odonata during a stay of two months m Cambridge; to Dr R T. Jackson, of Harvard University, for similar privileges in the study of the fossil Odonata of the same museum; to l^i'-!'• ?• Calvert, of the University of Pennsylvania, for the loan of valuable specimens; to Monsieur R. Martin, of Le Blanc, for the gift ot speci-mens-and to Dr. S. H. Scudder, for the privilege of examining the types of fossil Odonata in his collection, and also some of his original unpublished drawings. Proceedings U. S. National Museum, Vol. XXVl-No. 1 331 . 703
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