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Comstock adopts Meinert’s view that the elytra are not true fore wings, but gives no reasons. (Manual, p. 495.)

Dr. Sharp,^[25] however, after examining Dyticus and Cybister, affirms that this structure is only a part of the elytron, to which it is extensively attached, and that it corresponds with the angle at the base of the wing seen in so many insects that fold their front wings against the body. He does not think that the alula affords any support to the view that the elytra of beetles correspond with the tegulæ of Hymenoptera rather than with the fore wings.

That the elytra are modified paraptera (tegulæ) is negatived by the fact that the latter have no muscles, and that the elytra contain tracheæ whose irregular arrangement may be part of the modified degenerate structure of the elytra. Kolbe finds evidences of veins. The question may also be settled by an examination of the structure of the pupal wings. A study of a series of sections of both pairs of wings of the pupa of Doryphora and of a Clytus convinces us that the elytra are the homologues of the fore wings of other insects.