LI0HENE8. 399 



threads {sterigmata), which line the inside of the wall (Fig- 

 203, D) ; upon the sterigmata are borne large numbers of 

 minute cells (the spermatia), which fall off and are per- 

 mitted to escape through the small opening at the apex of 

 the spermagonium. It is unknown whether these germinate 

 or not ; some botanists have supposed them to be sexual in 

 their nature — hence their name, spermatia ; the recent in- 

 Testigations of Stahl, to be referred to below, seem to indi- 



Fisf. 205.— Germination of the spores of licliens. a, ripe ascospore of Megal- 

 ospdra a^nis ; 6 and c, successive stages of germination, seen in optical section ; 

 dy still later sta'ze of germination, seen in perspective, e, beginning of germination 

 of ascospore of Ochrolechia paXlesc&ns ; f, the same at a much later stHge, show- 

 ing the many young hyphie, mncli less magnilied. gr, half of an ascospore of P&r- 

 tusarlfi ceuihocarpa? seen in optical section, showing the pores in the endO!?pore 

 through which the hypha; p iss out. The exospore is shaded in the figure. / X 

 190, the others X 390.— After De Biiry. 



Gate the truth of the theory that they are the male sexual 

 elements ; on the other hand, their analogies to the similar 

 organs of Helvellacem and Pyrenomycetes point rather to 

 their conidial nature. 



Still other cavities (pycnidia) occur, in which spore-like 

 bodies are found, differing in size and other characters from 

 the spermatia. 



