156 



PYRENOMYCETES 



[CH. 



In due course the archicarp becomes surrounded by a sheath of vegetative 

 hyphae within which its growth is continued so that a mass of cells is pro- 

 duced from which asci at last arise. In the meantime the sheath becomes 

 differentiated into an outer coat of relatively large, brown-walled hyphae, 

 and an inner layer of smaller cells which become narrow and elongated. As 

 development proceeds a cavity appears within the perithecium, usually just 

 above the ascogenous cells, and branches from the lining mycelium grow 



out to form the periphyses; paraphyses 

 are not produced (fig. 114). 



The ripe spores are shed into the 

 cavity of the perithecium, and do not 

 reach the exterior immediately on leav- 

 ing the ascus. 



In addition to the above, two or 

 three other species have been examined, 

 and show the same type of archicarp 

 and of perithecium, but in no case has 

 any further cytological detail been 

 worked out. 



The uninucleate species in particu- 

 lar would probably repay investigation 

 and special attention ought to be given 

 to the septation of the archicarp and 

 to the number of cells from which ascogenous hyphae originate. 



114. Chaetoniiuvi Kunzeamim Zopf; 

 perithecium, x 200 ; after Zopf. 



CHAETOMIACEAE : BIBLIOGRAPHY 



1881 Zopf, W. Zur Entwickelungsgeschichte der Ascomyceten. Chaetomium. Nova Acta 



Acad. C. Leop.-Carol. G. Nat. Cur. xlii, p. 199. 

 1887 Olt.manns, F. Ueber die Entwickelung der Perithecien in der Gattung C/w^/owzkwz. 



Bot. Zeit. xlv, p. 193. 

 1907 Dange.\RD, p. A. RechercTies sur le d^veloppement du perithfece chez les Ascomy- 



cetes. Le Botaniste, x, p. 329. 

 191 1 \'all0RY, J. Sur la formation du p^rithfece dans le Chaetomium Kicnzeanum Zopf. 



van chlorinum Mich. Comptes Rendus, cliii, p. 1012. 



Sordariaceae 



The Sordariaceae are mainly coprophilous ; their perithecia are typically 

 free, sometimes superficial, sometimes so deeply embedded in the substratum 

 that little more than the neck protrudes from it. The genus Hypocopra is 

 exceptional in possessing a small stroma in which the perithecium is 

 immersed, but it resembles Sordaria in all other points. The present family 

 differs from the Chaetomiaceae in bearing only short filaments instead of 



