Lecture III —41— Fungal Endophytes 



chestnut at Nancy in France. Reess (1880) observed coralloid 

 clusters of mycorrhizae on pine bound with mycelium of Elaphomyces, 

 while Lewton-Brain (1901) described mycorrhizae of pine formed 

 in conjunction with E. variegatus. Since then interest in Elaphomyces 

 has languished. 



The genus Tuber also attracted observers, e.g. Frank (1888) who 

 observed T. aestivum on beech; and more latterly Costantin (1924) 

 who found that ascospores can be formed by the fungi apart from 

 mycorrhizal symbiosis. Mattirolo wrote a number of papers on truf- 

 fles, finding (1934) the mycorrhizal fungus of the introduced Popu- 

 lus canadensis to be T. Borchii; and he suggested the possible intro- 

 duction of fungus with the tree when the latter was brought to Italy 

 from California. 



Hemibasidiomycetes : — Of the Hemibasidiomycetes may be 

 noted the following: Weber (1884) assigned the fungus responsible 

 for tuber formation in Juncus to Entorhiza of the Tilletiaceae. Lag- 

 erheim (1888) described a new species of Entorhiza from roots of 

 Juncus articulatus obtained in Switzerland. The fungus had caused 

 the roots to form into galls, and within was an abundance of yellow 

 "spores". In the Black Forest similar nodules were found on the 

 same species of rush, and similarity to leguminous nodules was pointed 

 out. Formation of nodules on several species of Juncus was 

 noted by Schwartz in 1910. 



Hymenomycetous Mycorrhizal Fungi: — These are the chief 

 mycorrhizal fungi. Upwards of 50 genera of Hymenomycetes have 

 been reported as forming mycorrhizae (or perhaps it should be said, 

 incriminated in their formation) ; but in most of these cases there 

 are only one or two species cited in one or two reports. The principal 

 "mycorrhizal fungi", if numbers of reported species mean anything, 

 are Boletus, Amanita, Lactarius, Cortinarius, Russula, and Tricholoma. 

 Commencing with Frank's (1888) observations on Boletus bovinus 

 with spruce, later observers — almost all since 1920 — have shown by 

 field observation and synthetic experiment the connection of about 

 30 species of boletes with various trees. In a few cases a bolete has 

 failed to form mycorrhizae in synthesis, as B. edulis with pine and 

 spruce (MoDESs, 1941) ; while B. parasiticus is a parasite as the name 

 indicates (Smotlacha, 1911). Smotlacha believed that certain 

 boletes are confined to the neighbourhood of certain trees, as B. 

 rufus with aspen and B. rugosus with beech. 



The Agaricaceae are much investigated mycorrhizal fungi, al- 

 though Agaricus itself provides few members that are endophytes. 



