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ERIKSSON’S RECENT RESEARCHES on 
THE VEGETATIVE LIFE OF THE CEREAL 
RUST FUNGI.* 
By Charles B. Plowright, M.D. 
In the present communication the author points out that since 
the ’sixties, when De Bary made public his work on the life. 
history of the three common Pucciniae parasitic upon the cereals 
of Europe, continued experimental researches have shown that 
these three species consist in reality of no fewer than twelve. 
He further indicates that De Bary’s work, important and accurate 
as it was, deals with the three species then known as P. graminis. 
straminis, and coronata, in which he showed their relationship to 
the three common Aécidia on Barberry, Anchusa and Rhamnus, 
It did not afford an explanation of the manner by which in large 
areas of country the crops are simultaneously attacked by these 
rust and mildew parasites. He emphasises the fact so well 
known to those who study fungi in the field, that the area of 
infection does not extend much beyond 50 or 60 yards from a 
Barberry or Buckthorn bush. He further urges again that his 
hypothesis of a mycoplasmic symbiosis existing between the 
fungus and the host-plant explains the widespread dissemination 
of these parasites better than any other. His view is that this 
“ mycoplasm ” exists as a form of protoplasm (see Fig. A.) within 
the cells of the host, which can be demonstrated in those varieties 
of Wheat that are speciallysubject to the parasite, as soon as the 
first green leaf appears above ground. That this mycoplasm 
lives symbiotically in the tissues of the plant until such time as 
favourable conditions, climatic and other, cause it to pass into 
the typical mycelial stage from which the spore-beds of the Uredo 
are formed. If this can be shown to be the case, an explanation 
of those sudden and widespread outbreaks of Wheat-mildew 
which sometimes occur in England and the annual decimation 
which Wheat-rust causes in Australia and other countries become 
explicable, and, what is of infinitely more importance, it would 
give us a clue as to what lines on which we should fight the 
disease. 
* (Uber das Vegetative leben der Getreiderost pilze, Jakob Eriksson. I. 
Puccinia glumarum von Jakob Eriksson und Georg Tischler with three coloured 
plates; 4to. 1904. Stockholm: P. A. Norstedt & Sons. London: William 
Wesley & Son, 28, Essex Street, Strand.) 
