2 HUMPHREY 
The author wishes to acknowledge his obligations to Pro- 
fessor Douglas H. Campbell and Associate Professor George 
J. Peirce under whose direction the work was pursued. Thanks 
are also due Professor Alexander W. Evans, Dr. Marshall A. 
Howe and Professor Roland Thaxter for assistance in the 
determination of material and for the use of certain hepatice 
sent to the writer. 
PARASITISM AND SAPROPHYTISM IN HEPATICZ. 
The association of certain fungi with hepatice was first 
described in detail by Leitgeb,’ who, in his studies on Pézlidium 
ciliare, observed the infection of young sporogonia. He found 
that all such sporogonia were more or less abnormal in their 
mode of segmentation and inferred from this that the infected 
organs were structurally effected by the action of the fungus. 
Following Leitgeb, a number of writers have observed fungus 
infection in other hepatice. As early as 1879, Kny’ discovered 
sterile fungal hyphe in the rhizoids of Lunularza and Mar- 
chantia. ‘These, he states, were found to be present in rhizoids 
undergoing a process of regeneration, which process may have 
been stimulated by the hyphz. Cavers*® has observed that 
when Marchantza and Lunularia grow in ordinary soil free of 
humus the rhizoids are penetrated by hyphe which grow up- 
ward as delicate filaments showing cross-walls at rather long 
intervals. These hyphe occasionally become branched but 
never, so far as he has observed, reach the tissue of the thallus. 
On the other hand, he has found that when these plants grow 
on humus soil the hyphz extend into the compact tissue of the 
thallus, to which in fact, they are largely confined. 
Golenkin * observed the presence of endotrophic mycorrhiza in 
Marchantia palmata, M. paleacea, Preissia commutata, Tar- 
1Leitgeb: Untersuchungen iiber die Lebermoose, Heft 2, p. 58; Tafel 3, 
Fig. 26. 
*Kny and Bottger, 1879: Ueber eigenthiimliche Durchwachsungen an den 
Wurzelhaaren zweier Marchantiaceen. Verhandl. d. bot. Vereins d. Prov. 
Brandenburg, p. 2 of Separate. 
3 Cavers, 1903: Saprophytism and Mycorrhiza in Hepatice. The New Phy- 
tologist, Vol. II, No. 2, pp. 32-33. 
4Golenkin, 1902: Die Mycorrhiza ahnlichen Bildungen der Marchanteen. 
Flora, Band 90, p. 209. 
if 
