Vol. 49 / No. 6 
BULLETIN 
OF THE 
TORREY BOTANICAL CLUB 
JUNE, 1922 
Mycological notes for 1920* 
L. O. OVERHOLTS 
. (WITH PLATE 9 AND FOURTEEN TEXT FIGURES) 
1. ZYTHIA RESINAE (Ehrenb.) Karst. 
For several years there has been noted in the mountains 
near State College a small inconspicuous fungus always confined 
to resin exudate on species of two- and three-needle pines. It 
has been found especially abundant in the vicinity of Charter 
Oak and Greenwood Furnace, Pennsylvania. Its habitat is 
the resin mass inhabited by the larvae of the ‘pitch midge,” 
Cecidomyia resinicola Osten-Sacken. The origin of the resin 
exudate has not been studied by the writer, but E. P. Feltt 
states (on the authority of Miss L.S. Eckel) that the resin flow 
from the tree is not the result of an injury caused by the 
midges, but that they ‘‘take advantage of normal exudations 
of resin on which to oviposit,” although ‘‘the flow of this 
substance may be increased to some extent by the larvae 
rasping the living tissues.” At any rate the final resin masses 
are subglobose or depressed globose and 1.5-2.5 cm. in diameter 
(PLATE 9, FIG. 2). They may occur on one side of the limb only, 
as stated and illustrated by Felt, or the exudate may entirely 
encircle the limb, though I have seen no instances of the saccate 
type of resin mass illustrated by. Felt. These masses are in 
*Contribution from the Department of Botany, The Pennsylvania 
State College, No. 38. ‘‘Some mycological notes for 1919’’ was published in 
Mycologia 12: 135-142. 1920. 
TN. Y. State Mus. Memoir 8: 410-412. 1906. 
[The BuLLETIN for May (49: 123-162. pl. 5-8) was issued June 15, 1922.] 
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