Reproduction of Cystopus Cctndidus , Lev, 297 
Ceylon, Victoria, New Zealand, Brazil, Cuba, the United 
States, Canada, the Falkland Islands, Surinam, and British 
Guiana. 
The number of British species in addition to C. candidus is 
not numerous. In Massee’s c Phycomycetes and Ustilagineae ’ 
the following are given : — 
C. Tragopogonis , Schroet. 
C. Tragopogonis , var. spinulosus (C. spinulosus of De Bary). 
C. Lepigoni , De Bary. 
De Bary was the first to give us an account of the life- 
history of the plant, although, in the light of our recent 
knowledge, it is wanting in completeness. As his description 
is exceedingly clear and interesting however, I propose to 
give here a short account of the observations which he made 
in following out the life-history on fresh specimens. 
The Fungus is commonly known as White Rust, and 
appears as spots or pustules on all parts except the roots 
and seeds. It attacks especially the stems and seed-capsules. 
It causes generally a large amount of hypertrophy of the 
organ attacked, which is sometimes visible even before the 
white patches are seen 1 . The filaments of the mycelium 
penetrate the tissues of the plant in the intercellular spaces. 
The walls are composed of cellulose, and are often thick and 
gelatinous. Small globular haustoria are produced frequently 
and penetrate the walls of the parenchymatous cells of the 
host, and come to lie just inside the cell-wall. They are 
spherical bodies about equal in diameter to the filaments of 
the mycelium or not so large. They are at first full of proto- 
plasm, but later they contain only a watery fluid, and their 
membrane becomes thick and highly refractive, which makes 
them appear on a cursory examination like grains of starch. 
These organs are never wanting, and are so characteristic 
that one can often determine the presence of the mycelium by 
means of them. 
The oogonia are formed by terminal or intercalary swellings 
1 I have often found such swellings to contain numerous sexual organs. H. W. 
X 2 
