ASCOMYCETES 



379 



trichogyne is fertilised by the contact with it of one of the young hairs. 

 The perithece contains a number of asci, and these eight or twelve double 

 ascospores. The ripe double ascospore attaches itself to a fresh host by 

 one of its ends, and develops into the new plant. 



FIG. 312. A : b h, Stiginatomyces Bacri Peyr. (St. Musca Karsten). A, optical longi- 

 tudinal section of ripe specimen with organ of attachment at base ; the asci are seen 

 through wall of perithece. a, everywhere the appendage ; />, an isolated ascus with spores ; 

 c h, stages of development of perithece and appendage in order of letters. , Laboiil- 

 benia JJagellata Peyr. , the appendage. (A, c, g, h X 350 ; b, d, e,f x 450 ; B x 125.) 

 (After Peyritsch.) 



2. EXOASCUS (Fiickel). The species of Exoascus mostly attack 

 fruits, and set up in them sometimes conspicuous deformities. While 

 some of them possess a mycele which penetrates the parenchyme of the 

 fruit, &c. (e.g. E. Pruni, Fckl., E. deformans, Fckl.), others extend no 

 farther than between the cuticle and the epiderm-cells. In the former 

 case the terminal cells of the hyphae which emerge from the surface 



