I'UC'i IMA. 347 



suppre-sinn of secondary vasa, mucilage canals, and calcium 

 oxalate." 



The deformation induced by /'. fnr<,,,ut<i on /,'//"////<//* cathartica 

 wa> in\v>tiv.ated by Fent/lh. The changes were relatively 

 slight: the parenchymatous cells of the rind were enhuged 

 and separated hy large intercellular spaces : so also tin- paren- 

 chyma of the hast ; vessels were more nuiin-r<'U- in the \\ ..... 1 

 affected : the epidermal cells in some parts of the leaf were 

 broadened and those of the ine>..phyll enlarged. abnormally 

 shaped, and with huge intercellular spaces; in di>ea-ed leal- 

 stalks the epidermal cells are thinner-walled and l.roader, while 

 all parenchymatous cells become enlarged, thinner-walled, and 

 with many intercellular spaces; the fibro-vascular bundles are 

 enlarged, chiefly from an increase of the wood-parenchyma : this 

 tiue, in normal petioles, occurs as single m\\s nf cell- running 

 radially between the vessels, whereas, in diseased jilaee-. three 

 parallel layers of cells may separate neighbouring ves M -ls. 



P. dispersa Eriks. et Henn. I'.mwn-ru.-t. (I'.i'itain.) Thefulluw- 

 ing .-jiei-ialixed varieties of this species have lieen distinguished: 



Ser. I. Aecidium on An<-]nix arvensis and A. <>jfi<-i/tli* (Aec. 

 a Hi-It n.^,1 ^ ). 



1. \'ar. secalis on tf<-r<il, cereale? 



Sep. II. Aeeidium unknown. (Whether distinct varieties, 

 somewhat uncertain.) 



1*. Yar. /////// mi Tritii-imi ruli/,/ ,<. 



.".. \'ar. In-ouii on J3r<>itinx nrri-ni* (and ]!/. brizaeformis). 



4. \'ar. "//' V YV/'''' " n Ti-itii-nin repens. 



P. rubigo-vera (!>.('.)( /'. straminis Fuck.. /'. striaeformis \\'e-t. i. 

 il'iiitain and !'.>. A.merica.) This, in its uredo- and teleut- 

 stages, frequents varinii> grasses, \\hile the aeeidia occur \\ 

 ineac. A \arietyon species \' //<>,;/, ,/,/* has been 

 /'. .s/'//////< -. The teleutospore-patches arc enveloped in 

 lirowii pai'aphy- -s : the t eleiit p<>! 'e- l;a\e \ er\ >liuM Malks. 



The anatomical changes jtrodueed in Leaves he-et with aeeidia 



liaVe beell >ta|ed h\ \\:dxke|' as fiilluU-: The SWcllillU "I the 

 le.il'-pet iole- i- dlle In ell la Pj e|||e| 1 1 "(' their eelN. the 1. 



intercellular space-, ( ,f the spongy ]iareiiehy ma aie n Imi-er 



,', ///'/"./ i 1 1 I-' i . il.in . . 188 



I "illnl ;ilun- with lln- .1 i-i'/unn at Moul, - ..tlunli l.\ l'i..|. .1. \\ . 



Tr.iil. i 



