Ward. — Recent Researches on the Parasitism of Fungi. 1 7 
included with the next nine species in P. Rubigo-vera , DC., but it has no aecidium 
form as yet known. There are at least five specialized forms of it, as follows : 
F. sp. 1. Tritici , on Wheat; but not on Barley, Oats, or Rye. 
F. sp. 2. Secalis , on Rye, but not on Wheat, Barley, or Oats. 
F. sp. 3. Hordei , on Barley, but not on the other cereals. 
F. sp. 4. Ely mi, on Elymus. 
F. sp. 5. Agropyri, on Couch Grass. 
Species IV. P. dispersa , Er. This is the Brown Rust of Rye, and is heteroecious 
on Anchusa, where it produces the Aecidium asperifolii of previous authors. 
Species V. P. triticina , Er., the Brown Rust of Wheat, has no aecidium as yet 
known, and is not heteroecious on Anchusa. 
Species VI. P. bromina , Er., is the Brown Rust of the Bromes. Its aecidium is 
as yet unknown. [Since this was written, F. Muller has shown that the aecidium 
is formed on Symphytum and Pulmonaria , &c.] 
Species VII. P. Agropyrina , Er., is confined to Agropyrum repens , and has no 
known aecidium. 
Species VIII. P. holcina , Er., is confined to Holcus, and no aecidium is known. 
Species IX. P. triseti \ Er., occurs only on Trisetum flavescens , and has no known 
aecidium. 
Species X. P. simplex , Kcke. Er. and Henn, is a dwarf species, hitherto regarded as 
a variety of P. Rubigo-vera , DC., occurring only on Barley and with no known aecidium. 
Species XI. P. coronifera , Kleb., was previously confused with P. coronata , Corda. 
It is the Crowned Rust of Oats, &c. It is heteroecious on Rhamnus catharticus ; 
but not on R. Frangula. There are at least six specialized forms, as follows : 
F. sp. 1. Avenae , on Oats. 
F. sp. 2. Alopecuri, on Alopecurus. 
F. sp. 3. Festucae , on Festuca elatior. 
F. sp. 4. Lolii, on Lolium perenne. 
F. sp. 5. Glyceriae , on Poa aquatic a. 
F. sp. 6. Hold, on Holcus. 
Species XII. P. coronata , Corda, the Crown Rust proper, produces its aecidium 
on Rhamnus Frangula , and has at least five specialized forms, as follows : 
F. sp. 1. Calamagrostis, on Calamagrostis arundinacea , &c. 
F. sp. 2. Phalaridis , on Phalaris arundinacea. 
F. sp. 3. Agrosiis, on Agrostis stolonifera. 
F. sp. 4. Agropyri, on Couch Grass. 
F. sp. 5. Hold, on Holcus. 
Species XIII comprises a third species of the P. coronata group ; with two forms, as 
follows (neither has any known aecidium, and they were previously included with the 
two preceding species under P. coronata) : 
F. sp. 1. Epigeii, on Calamagrostis Epigeios. 
F. sp. 2. Melicae, on Melica nutans. 
That we must accept these data as the experimental results of a good 
investigator is unquestionable ; but there is room for differences of opinion 
C 
