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The Ohio Naturalist. 
[Vol. II, No. 7 , 
a mere enlargement of the tip of the stem, and containing one or 
more larval chambers. Examination of section under a compound 
microscope, however, reveals a condition similar to that described 
for C. solidaginis and C. s.-strobiloides. Each larval chamber is 
in reality the apex of a bud. The young leaves of the bud are 
closely applied to each other and their structure unaffected by the 
insect. As the gall developes the leaves do not unfold but assume 
a corky texture and in the fully mature gall their identity is 
almost lost. 
It is very evident that the larval chamber occupies a correspond- 
ing position in each of these galls. The insect prevents the 
elongation of the stem, thus causing the leaves of the apical 
bud to be bunched and reduced in size. The fact that the leaves 
of the Solidago reach the greatest development and those of 
the Quercus the least development is probably due to the char- 
acter of the plants. Of these three plants the growth of the 
Solidago is the most rapid while that of the Quercus is the slow- 
est. In Solidago the rapid growth may be sufficient to overcome 
the injury and cause the bunch of leaves ; in the Salix where the 
growth is not so rapid the leaves are smaller and more compact ; 
in the Quercus where the growth is slowest the bud never opens 
but becomes corky and the leaves gradually lose their identity. 
This work was pursued during the year 1901-2 in the Zoolog- 
ical Laboratory of the Ohio State University under the direction 
of Professor Herbert Osborn to whom I am indebted for many 
valuable suggestions. 
LITERATURE. 
Only those references which were especially useful in preparing 
this paper are cited. 
1. Adler, Hermann, M. D., “ Ueber den Generations — wech- 
sel der Eichen Gallwespen” Zeitschrift fur wisseuschaftliche 
Zoologie. Bd. 35. Leipzig “Alternating Generations, a 
Study of Oak Galls and Gall Pdies,” translated by C. R. Stratton. 
Clarendon Press, Oxford. 
2. Ashmead, W. H. “A Bibliographical and Synonymical 
Catalogue of the North American Cynipidae with descriptions of 
new species.” Transactions American Ent. Soc. Vol. XII, pp. 
291-304. 
3. Ashmead, W. H. “ Synopsis of the North American Sub- 
families and Genera of Cynipidae.’’ Trans. Amer. Ent. Soc. Vol. 
XIII, pp. 59-64. 
4. Ashmead, W. H. “On the Cynipidous Galls of Florida 
with descriptions of new species and Synopsis of the described 
species of North America.” Trans. Amer. Ent. Soc. Vol. XIV, 
pp. 125-158. 
5. Bassett, H. F. “Description of several supposed new 
species of Cynips, with remarks on the formation of certain Galls. 
Proc. Ent. Soe. of Phil. Vol. II. No. 3, pp. 3 2 3 “ 333 - 
