Kelley — 20 — Mycotrophy 



ported by several workers, the latest (Stark, 1925) finding the plant 

 with endophyte in the Leningrad Gardens. In Archangiopteris, as in 

 several others ferns, West (1917) found a new fungus that produced 

 under natural conditions distinct reproductive bodies other than 

 vesicles. Marattia itself, although reported non-mycorrhizal by Stahl, 

 is attested by several later workers. Campbell (1908) states posi- 

 tively the presence of endophyte in green prothallia of M. Douglassi 

 besides those of several other Marat tiaceae, including Kanlfussia aes- 

 culifolia which West (1917) confirms for the sporophyte plant. West 

 also describes and figures infection for Danaea alata and D. nodosa, 

 neatly demonstrating apparent phagocytosis within the outer layers of 

 cortex. 



The leptosporangiate ferns have been less studied but are not with- 

 out their endophytes. Two genera of the Osmundaceae have been 

 studied, van Tieghem as early as 1870 reporting mycelial hyphae of 

 a parasite coiled about dark masses in large cells of the inner zone 

 of cortex of Osmunda regalis and several other ferns. Strangely 

 enough, Stahl asserts that this species is not mycorrhizal and no one 

 else has made a later statement. Campbell, in his studies of fern 

 prothallia, found that many cells in O. cinnamonea and 0. Claytoniana 

 contain an endophyte which consists of large non-septate hyphae that 

 are strictly intracellular. For the sporophyte of the last species, Loh- 

 MAN (1927) says that an endophyte is absent. In an excellent paper 

 on Todea harhara, Cribbs (1920) notes that an endophytic fungus 

 was found to occur frequently in the cortical tissues of the root exter- 

 nal to the endodermis and internal to the sclerenchymatous cells of the 

 peripheral region. It was found to gain entrance by root hairs and also 

 by dissolving its way through the epidermal cell-wall at the edge of 

 the root-cap. Cribbs gives us neat figures which beautifully delineate 

 apparent digestion stages. 



For the Gleicheniaceae our only author is Campbell, who mentions 

 five species of Gleichenia that have mycothallic prothallia. Two au- 

 thorities sponsor the Cyathaeaceae, those Tree ferns of the tropics: 

 Janse found Cyathaea mycorrhizal in Java, pelotes and sporangioles 

 being found in 3-4 layers of cortex; while Asai (1934) reports C. 

 spimdosa as mycorrhizal, and also Alsophila formosana and A. 

 pusttdosa. 



The Polypodiaceae offer a hopeful although little touched field, for 

 most of these ferns live in humus soil and might be expected to har- 

 bour endophytes ; yet we suspect that lack of economic utility of ferns 

 accounts for aversion to their study. 



Amongst wildlings of the American prairies, Lohman (1927) 

 gathered some casual specimens of fern and reported briefly as to 



