DIM OMYCETES. 241 



Tlie paraphyses aiv developed from tin- mycelium of the 

 envelope ami occupy the interim- of the ascocarp, \vhilr the 

 asci arise later IVoni the ascogenous hyphae and force their way 

 in. The formation of asci and paraphy-ev may -jn> on \'v a 

 lonu time. I'eriphyses are m>t produced. 



The Discomycetes include live divisions, the /'//</"//.//."., 

 Wu-tiili<\ Ti-i/l>li<H,<n\ Dermateaceae, and Pezizeae. .Many of 

 the species included in these are parasitic on eryptniMinie 

 plants to form lichens, tlie majority are saprophyte-, and mily 

 a few isolated ^ronjis are true parasites mi higher plant-. The 

 latter lielong to the I'/inn',/;,!,;,!, . Dermateaceae, and Pezizeae. 



(1) PHAi IDIACKAE 



The apothecia are Mack and thick-walled, at first embedded 

 in their sul><tratum, hut later hreakinu' through it. The asco- 

 -enous layer is spread out on a delicate Hat hypothecium. 

 The lilack apothecia of the species of I'lun-iil'inm are frequent 

 on leaves and needles. 1,'ehni divides the -nmp into two 

 families: the Enj>li<i<-i,ri, <i. and the Pseudophacidieae. 



EUPHACIDIEAE. 



The apothecia are emhedded in the tissues of the lio>t : the 

 superincumbent Layers of the suhstratum form in- over them a 

 olackish iiieml>raiioii> plale, which is ruptured into lol,e- ami 

 exposes the Mack apothecia] disc. 



Phacidium. 



The apothecia ale I'used with the -iiperincuniheni Layers of 

 the ho-t -plant, ami the lilack cover 80 formed i- ^plii into 

 .-evend lolie<. The e] 1 1 1 i--ha pei 1 asci contain ei-ht colour!' 

 unicellular, ovoid or >pindle-vhaped spores. The paraphx 



aie filamentous. The p,,r,. of the ascus i- coi,,ured hlue liy 

 iodine. 



Phacidium repandum I-V. (Britain) Occurs on li\ncj Leaves 



and ^leln-; of .1 ;JH i-ii/<t ,/,,,;! f,t , 1,'n/ll/ill llln/l it,/,,. alld other 



Rubiaceae. The pyenidial form i prohaMv /'/ii/ll'n-/, 



punctiformie I-V. 



