April, 1904 .] Galls and Insects Producing Them. 14 1 
mature, but the cells lining the larval chamber were well supplied 
with protoplasm, and numerous short trichomes were developed 
from the dorsal surface and extended into the chamber. Tannin 
was very abundant. 
The gall of Cecidomyia tubicola O. S. on Hicoria ovata (Figs. 
117a, b, c) is very similar to C. holotricha, except that the amount 
of tannin is not so great. The upper wall of the gall is much 
thicker than either the side or lower wall. The point of attach- 
ment is not so large, but the gall is protected bj’ a growth pro- 
ducing a cup-shaped cavity in which the gall is developed (Fig. 
117a). The inner la}'ers of cells are ver}" rich in protoplasm. 
The cells are elongated in the long axis of the gall and fibro- 
vascular bundles are more numerous than in C. holotricha, but 
are very small. The cup-shaped structure (117c) in which the 
gall is formed is composed of elongated cells. The pali.sade cells 
in that part of the leaf opposite the gall are unaffected. 
Cecidomyia viticola O. S. (Fig. 118) has the same general 
character as C, tubicola, but is much longer. 
Sciara ocellaris O. S. is one of the simplest of the Cecidomyidae 
galls. The larva does not penetrate the tissues of the leaf, but 
confines its attack to the outside, causing an indentation on one 
surface of the leaf and a corresponding elevation on the opposite 
surface (Fig. 119a) and also causing a very slight thickening. 
The structure ( Fig, 119c) when compared with that of the normal 
leaf (Fig. 119b) shows the palisade transformed into ordinary 
mesophyll and the intercellular spaces entirely obliterated. It 
therefore corresponds in structure to the simple leaf-curl galls 
produced by some of the Aphididae (e. g., Schizoneura Ameri- 
cana Riley, Part i. Fig. 12). 
3. GALLS OF THE CYNIPIDAE. 
My specimens of Rhodites bicolor Harris ( IHg. 120) were well 
developed when collected. I was therefore unable to determine 
the early structural characters. The structure in these galls evi- 
dentl}’ does not show the four well defined zones so characteristic 
of this family. The inner cells are well supplied with nourish- 
ment for the large number of larvae. 
The galls of Amphibolips conflueutus Harris are verj- large and 
have a single larval chamber in the center. The nutritive and 
protective zones (Fig. 121a) can be distinguished, but are not so 
well defined as in the closely related species. A, inanis (Part I, 
P'igs. 28a, b). The parenchyma and epidermal zones ( log, 121b) 
are well defined and the space in the parenchyma is filled with a 
cottony-like substance which upon close examination is composed 
of fibro-vascular bundles (as in A. inanis, Figs. 28a, b, and H. 
centricola. Figs. 27a, b, c) and of long, unicellular threads (Fig. 
i2ic), as ill C. papillatus (Figs. 30a, b, c and 81). 
