1 5 6 



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 otherspecieshave 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. 



Fig. 114. Chaetomium Knnzeanum Zopf; 

 perithecium, x 200 ; after Zopf. 



CHAETOMIACEAE : BIBLIOGRAPHY 



1881 ZOPF, W. Zur Entwickelungsgeschichte der Ascomyceten. Chaetomium. NovaActa 



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

 1887 OLTMANNS, F. Ueber die Entwickelung der Perithecien in der Gattung Chaetomium. 



Bot. Zeit. xlv, p. 193. 

 1907 DANGEARD, P. A. Recherches sur le deVeloppement du perithece chez les Ascomy- 



cetes. Le Botaniste, x, p. 329. 

 1911 VALLORY, J. Sur la formation du pdrithece dans le Chaetomium Kunzeanum Zopf. 



var. chlormum Mich. Comptes Rendus, cliii, p. 1012. 



Sordariaceae 



The Sordariaceae are mainly coprophilous ; their perithecia are typically 



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



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



:ceptional in possessing a small stroma in which the perithecium is 



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



ffers from the Chaetomiaceae in bearing only short filaments instead of 



