346 UREDINEAE. 



Puccinia coronata ('(nda. (Ihitain and U.S. America.) 

 Eriks.son, iVoin hi.s own expeiiuionts and those of Klebahn, 

 distinguishes llie I'ollowini; specialized varieties: 



Ser. I. Aecidia on lihamnus cathartica, Rh. clacoidcs, Bli. 

 yrandifolia, Rh. alnifolia {Puccinia coronifcra Kleb.). 



1 . Var. avcnae on Avcna sativa. 



2. ^'ar. alopccuri on AlojKcurus ^;r«<f?ms. 



3. A'ar. fcstucac on Fcstuca elatior (and F. ruhra). 



4. Var. lolii on Lolium perennc. 



In addition to these, Klebahn found a foi^ni on Avena elatior, and one 

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



Ser. IT. Aecidia on Rliammis Fnuigula {pHCcinia coronata I., 

 Kleb.). 



5. \q.x. calainagrostis on Caki'magrostis arundinacca (and 



C. lanccolata). 

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

 gibberosa Lagerh.), Agrostis vulgaris, Nolens lanatus (? If. mollis), and 

 Pkalaris arundinacea. 



Ser. III. Aecidia on RJiainnus (lalinrica {Puce, coronata var. 

 himcdensis, Barcl.). 



Indian forms on Brachypodium sylvaticum, {Piptatherum holclfonne, and 

 Festuca gigantea,) of which nothing more is known. 



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



6. Var. mclicae 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 RJiamnus 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 

 ' WiikUer. J'riiu/shehn's Jahrhnrh, 1892. 



