Page:Phylogeny of cynipid genera and biological characteristics.pdf/11



(continued)

The first set of figures is based on Dalla Torre and Kieffer's catalogue (1910) of the Cynipidae of the world, the second set on my own catalogue of the American Cynipidæ. My catalogue includes a wider recognition of synonyms and is brought more nearly up to date than Kieffer's. I have omitted two “species” of the Cynipini—Rhoophilus loewi Mayr, which is evidently an inquiline in the Rhus gall, and Solenozopheria vaccinii Ashmead, which I have reason to believe is not the true maker of the huckleberry gall with which the single specimen was taken.

Of all plant deformations, the galls inhabited by the gall-wasps show the most astonishing of elaborate and regular designs, and many theories have been invented to explain what may be the causes of such phenomena. Apparently the secret is still far from solution. I have nothing at this time to contribute on the subject, nor is it in point here to review the work of those who have tried to solve the question. What may be offered now is material to show that all of this elaborate organization of plant tissue has arisen within the history of the Cynipidæ alone, independent of any other group of gall-making insects, since a day when the family was merely plant-tissue-inhabiting, not yet gall-producing.

That the factors responsible for the form of the deformation are specific for the insect inhabiting the gall has always been recognized. The number of designs of these galls is about as great as the number of species of insects producing them. Occasionally two apparently different species of wasps will produce galls very nearly identical, but a careful