UBEDINE^. 



311 



hyplige, which penetrate between the cells, causing the leaves 

 to become usually much thickened and distorted in those 

 parts which are infested with the parasitic growths. Oc- 



Fig. 216, — Several stages of Puccinia grandnis. A. part of a vertical section of a . 

 leaf of the Barberry {Berberis vulgaris), with a young unopened aecidinm fruit ; w, 

 epidermis. J., section of a Barberry leaf, natural thickness at X, greatly tiiickened 

 from h toward y ; w, epidermis of the under surface ; o, of the upper surface ; », 

 unopened tecidium fruit ; a, a, a, opened gecidium fruits ; sp, sp^ spermagonia. II., 

 a mass of teleutoepores on a leaf of Couch-grass { Triticum repens) ; e,t\\Q ruptured 

 epidermis ; b, sub-epidermal fibres of the grass leaf. lU,, three uredospores, ur, 

 with one teleutospore, t ; sh, sub -hymenial byphse. All highly magnified.— J. and I. 

 after Sachs i //. and ///. after De Bary. 



casionally these hyphse are found in other parenchymatous 

 parts besides the leayes, as the petioleSj young stems, and 

 even the flowers and fruits. After a short time there form 



