Pole Evans. — The Cereal Rusts. 
457 
Miiller (26) (27) showed that the Aecidium of this species is formed 
on Symphytum officinale , L. and Pulmonavia montana , Lej., and for this 
reason it has now been called P. Symphyti-Bromorum by Klebahn. 
Not only is it to be distinguished by these physiological differences 
from P. dispersa on Rye, but as will be seen from my figures, the uredo 
mycelium of P. Symphyti-Bromorum is morphologically distinct from that 
of P. dispersa. 
As the histology of P. Symphyti-Bromorum has been very fully 
described by Marshall Ward (33) there is no need to devote any further 
space to it here, except to say that my observations entirely coincide with 
those of Marshall Ward. 
To avoid confusion in nomenclature it should be noted that this 
P. dispersa examined by Marshall Ward (33) is now known as P. 
Symphyti-Bromorum. 
Puccinia simplex (Kcke.), Erikss. and Henn. 
This is the brown or dwarf rust of the barley. It is very common 
on the barley fields around Cambridge, and is to be found there in the 
uredo stage all the year round. Up to the present I have not found 
this rust in South Africa. 
By the earliest observers it was distinguished under various synonyms, 
e.g. 
(P. straminis var. simplex Kornicke, 1865 ; Uromyces Hordei Nielsen. 
1875; P‘ anomala i Rostrup, 1876). 
However, Eriksson and Henning (16) have shown that it must be 
regarded as an independent species. 
In the field it is characterized by its extremely small and very 
scattered pustules, which in length are from -3—5 mm. and in breadth 
•1—2 mm. The uredospores are spherical to oval, with a brownish 
coloured membrane, which is distinctly spiny. They measure from 
20-30 [jl by 17-22 [jl. 
The teleutospores according to Klebahn are mostly one-celled, and 
germinate only after the winter’s rest. 
The Aecidium is as yet unknown, Klebahn during 1900 and 1901 
made sowings on some forty-three plants, but with no success. 
Klebahn (24) has found P. simplex on Hordeum vulgare , L., vulgare 
‘ cornutuml coeleste tidfurcatum, distichum , L., distichum ■- nigricans l 
hexastichum , L., zeocriton , L. 
The Histology of Uredo simplex (Kcke.), Erikss. and Henn. 
Klebahn (24) in two figures on the anatomy of this rust, shows 
the general appearance of the hyphae and some young haustoria. He 
