Identity of a Rust on Ephedra.
The aecial stage of a rust on Ephedra has been called a Peridermium. Clues as to its telial stage have been lacking. It is here described as resembling more a form of Roestelia, and the reasons for its possible relation to Gymnosporangium multiporum Kern are presented: the two sets of hosts have similar distributions: the two rust stages have the same geographic range; they have been found in close proximity in the field.
Kern
F D
FD
Keener
P D
PD