346 UREDINEAE. 



Puccinia coronata Corda. (Britain and U.S. America.) 

 Eriksson, from his own experiments and those of Klebahn, 

 distinguishes the following specialized varieties : 



Ser. I. Aecidia on Bhammts cathartica, Rh. elaeoides, Rh. 

 grandifolia, Rh. alnifolia {Puccinia coronifera Kleb.). 



1. Var. avenae on Avena sativa. 



2. Var. alopecuri on Alopccurus pratensis. 



3. Var. festucae on Festuca elatior (and F. rubra). 



4. Var. lolii on Lolium perenne. 



In addition to these, Klebahn found a form on Avena elatior, and one 

 on Holciis lanatus, in regard to whose specialization, nothing is known. 



Ser. II. Aecidia on Rhamnus Frangula (Puccinia coronata I., 

 Kleb.). 



5. Var. calamagrostis on Calamagrostis arundinacea (and 



C lanceolata). 

 In addition : forms on Dactylis glotnerata, Festuca sylvatica (? Puce, 

 gibberosa Lagerh.), Agrostis vulgaris, Holcus lanatus (? H. mollis), and 

 Phalaris arundinacea. 



Ser. III. Aecidia on Rhamnus dahurica {Puce, coronata var. 

 himalensis, Barcl.). 



Indian forms on Brachy podium sylvaticum, {Piptatheruin holciforme, and 

 Festuca gigantea^ of which nothing more is known. 



Ser. IV. Aecidia unknown, probably do not exist. 



6. Var. melicae on Melica nutans. 



Amongst our cereal crops the oat alone is attacked by this 

 species, and much damage may result. 



The uredo-patches have no paraphyses like the preceding 

 species, and they form reddish-yellow spots and stripes ; the 

 teleutospore-patches are black. The upper cell of the teleuto- 

 spores is surrounded by a crown of six or seven blunt teeth. 



The presence of aecidia on Rhamnus is accompanied by 

 thickening and twisting of young shoots, and blister-like de- 

 formation of leaves, calyces, and ovaries. Wakker' thus 

 summarizes his investigations on the anatomical changes induced 

 by the fungus on Rhamnus Frangula : " It causes the cells 

 of every part to become abnormally enlarged, at the same time 

 giving rise to an orange coloration of the cell-sap and an 

 accumulation of starch ; there is no longer any formation of 

 interfascicular cambium, and there is a partial or complete 

 ' Wakker, Pringsheim's Jahrhuch, 1892. 



