350 



UREDINEAK. 



Steins, leaf-stalks, and leaf-nervature often undergo one-sided 

 thickening and curvature as a result of formation of aecidia. 

 Wakker thus summarizes his observations on the anatomical 

 changes in these malformed parts of Urtica : there is an en- 

 largement of cells and an increase in the number of large inter- 

 cellular spaces ; no formation of collenchyma, interfascicular 

 cambium, and chlorophyll ; a diminished formation of calcium 

 oxalate ; an orange coloration of the cell-sap ; and a distension 

 or rupture of the epidermis. 



FIG. ISu. Puccinia, co.ricis on Stingiuy Settle. The aecidial cushions have caused 

 swelling and distortion of stems and leaf -stalks, also swollen outgrowths on the 

 leaves, (v. Tubeuf phot.) 



Klebahn and Magnus believe that there is a Puccinia on 

 Carex acuta and C. Goodcnoughii related to an Aecidivm on 

 Hibcs Grossularia, It. rubrum, and R. aureum ; also a Puccinia 

 on Carex riparia with an Aecidium on Ribcs niyrum. On this 

 account Klebahn l distinguishes Puce, caricis I., u., and in., 

 agreeing respectively with P. Prinysheimiana Kleb., P. caricis 

 (Sclium.), and P. Jl/nt/it/'xii Kleb. 



P. Schoeleriana Plowr. et Magn. 2 (Britain). Uredo- and 

 teleutospores on Carcx arcnaria: aecidia on Senetio Jacol><. 



, Zeitschrift f. PflanzenkrattMieitm, 1892, 1S94, ami 1895. 

 1886. 



