? 
437 
In Osmunda regalis, cinnamomea, and Claytoniana, and Todea 
vivularis the same parts are present, the true annulus being situated 
upon the dorsum of the sporangium. 
In all these families the sporangium is divided into halves at 
the time of dehiscence. The true annulus, the connectives and 
the lip cells perform identical functions in all. Were the annulus 
in any of them “ complete,’ the highly developed mechanism 
which now serves the fern so perfectly in the dispersion of the 
spores would be defeated. During the eversion of a “complete” 
annulus the lateral walls of the sporangium would be torn to pieces 
and the spores would fall to the ground before the spring took 
plate, and the present comparatively wide dispersion could not 
take place. 
BoraNicAL DEPARTMENT, CORNELL, UNIVERSITY, 
Notes Upon a New Exobasidium.* 
The genus Axodasidium is interesting in standing almost alone 
. aS containing parasites in the large group Thelephoree of the 
Hymenomycetous Fungi. Authors have differed as to the place 
the genus should hold in the classification, but Saccardo ignoring 
the views of Schroter and others, disposes of it as above stated. 
He describes eleven species, eight of which according to Farlow’s 
Index are American. Of these only one is upon a host outside of 
the Heath family, namely, Exobasidium Symploci, E. & M. on 
Symplocos tinctoria, L. Her. The American species on Ericaceze 
may be tabulated with the hosts as follows: 
1. Exobasidium Vaccinii (F1.} Woron. 
On Arbutus Mensziesii, Arctostaphylus Uva-ursi, Casstope tetra- 
ona, Gaylussacia resinosa, Rhododendron viscosum, Vaccinium 
macrocarpum, Vaccinium uliginosum, Vaccinium Vitis-Idaea. 
2. Exobasidium Andromeda, Pk. 
On Andromeda ligustrina. 
3. Exobasidium Azalee, Pk. 
On Rhododendron nudifiorum. | 
*Read before the Botanical Club, A. A. A. S., Madison, Wis., August, 1893. 
