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 as the alternate of folii. This error was corrected by further work which the same investigator undertook in 1878 and 1879 on potted plants indoors. Both Adler (1881) and Beyerinck (1883) described the ovipositor of the insect, which is fairly straight. The insect puts itself into a position to pierce the bud perpendicularly, laying but a single egg in each bud and usually requiring from ten minutes (acc. Beyerinck) to a half hour (acc. Adler) for the single oviposition. A droplet of a sticky secretion from the insect (acc. Beyerinck) fastens the egg inside the bud scales. It is not until the following March and April (acc. Beyerinck; end of April acc. Adler) that the first signs of gall formation are to be noted in these buds; but from 34 ovipositions Adler secured 11 galls which were well developed by the beginning of May. Adler's experiments were repeated in 1879, and left no doubt that the bisexual insect that alternates with folii is the bud gall inhabitant taschenbergi. Beyerinck confirmed these results in the autumns of 1880 and 1881 in Holland, adding many details concerning the insect biology, the gall histology, and the gall embryology.

Paszlavszky (acc. Kieffer 1901) noted the caraboid odor of the ovipositing females of the agamic folii. Perhaps these odors are similar to the pungent, acid odors emitted by so many of the agamic forms of American Cynips, especially the short-winged forms, when they are disturbed in any way at all.

The early development of the galls of the agamic folii has been studied by Beyerinck (1883) whose interesting diagrams are reproduced in the present paper (figs. 107-117). Beyerinck found that gall formation starts in the phloëm of the vascular bundles whose xylem is in contact with the egg. The new growth gradually develops within the vein, finally forming a canal which allows the young larva to pass from the xylem to the phloëm in which growth is proceeding. This is similar to the condition reported for other cynipid galls which originate from eggs that have been deposited deep in the vascular bundles, altho there is no formation of a canal for species in which the eggs are placed in the phloëm or cambium to begin with. Since the epidermis of the leaf does not directly contribute to the gall formation, the young gall ruptures the leaf epidermis to one side of the vein where the resistance is least. The larva has hatched before the rupture of the