GALLS PRODUCED BY TWO CEDAR RUST FUNGI 
249 
Summary 
The galls produced by G. Juniperi-virginianae and G. glohosuni 
on Juniperus virginiana originate as modified leaves. 
The vascular systems of the galls are composed of the enlarged 
and modified leaf-trace bundles. 
Acknowledgments 
Grateful acknowledgment is made to Dr. Donald Reddick for 
valuable suggestions and assistance and especially to Dr. Arthur J. 
Eames for assistance in the preparation of material, interpretation of 
slides and for criticism of manuscript. 
Department of Plant Pathology, 
Cornell University 
LITERATURE CITED 
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Juniperi-virginianae. Nebr. Agr. Exp. Sta. Rept. 25: 215-246. 1912. 
Farlow, W. G. The Gymnosporangia or Cedar Apples of the United States. Boston 
Soc. Nat. Hist. Anniv. Mem. 1880: 1-38. 
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1-73. 1915. 
Heald, F. D. The Life History of the Cedar Rust Fungus, Gymnosporangium 
Juniperi-virginianae Schw. Nebr. Agr. Exp. Sta. Rept. 22: 105-133. 1909. 
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Pammel, L. H. The Cedar Apple Fungi and Apple Rust in Iowa. Iowa Agr. Exp. 
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Reed, H. S. and Crabill, C. H. The Cedar Rust Disease of Apples Caused by 
Gymnosporangium Juniperi-virginianae Schw. Va. Agr. Exp. Sta. Tech. 
Bull. 9: 1-106. 1915. 
Sanford, Elmer. Microscopical Anatomy of the Common Cedar Apple (Gymno- 
sporangium macropus). Annals of Botany 1 : 263-268. 1888. 
Stewart, Alban. An Anatomical Study of Gymnosporangium Galls. Amer. Journ. 
Bot. 2: 402-417. 1915. 
Wornle, P. Anatomische Untersuchung der durch Gymnosporangium-Arten her- 
vorgerufenen Missbildungen. Forst. Nat. Zeitschr. 3: 129-172. 1894. 
EXPLANATION OF PLATES XII-XVI 
Plate XII 
Fig. I. Young galls caused hy Gymnosporangium Juniperi-virginianae showing 
their axillary position and their relation to the leaf. The two galls at the right 
were removed by pulling on the tips of the leaves to which they are attached. Com- 
pare the method of origin here with that shown for G. globosum galls in PL XV, Fig. 3. 
