170 



PYRENOMYCETES 



[CH. 



of conidiophores, from which small oval conidia are abstricted. In Xylaria 

 these form a white coating, in marked contrast to the older black portions 

 of the stroma, where the perithecia are maturing, and justify the name 

 candle-snuff fungus, applied to some of the commoner species. If, in either 

 genus, the stroma be sectioned during the conidial stage, nests of small 

 hyphae, similar to those in Poronia, will be found, and are the first indica- 

 tions of the perithecia. 



Sometimes a stouter hypha with larger nuclei, presumably an archicarp, 

 is recognizable (fig. 12S), but it has not been shown to function, and there 

 is no evidence of normal sexuality. It is however not unlikely that some 

 of these species, which are conveniently easy to microtome, will repay 

 further investigation. At a later stage ascogenous hyphae are readily recog- 

 nizable (fig. 129). 



Fig. 128. Xylaria polymorph/* (Pers.) 

 Grev. ; archicarp embedded in 

 stroma, x iooo. 



Fig. 129. Xylaria polymorpha (Pers.) Grev.; septate 

 archicarp, x iooo. 



XYLARIACEAE: BIBLIOGRAPHY 



1861-5 TULASNE, L. R. and C. Selecta Fungorum Carpologia; Imperial-typograph., Paris. 

 1900 Dawson, M. On the Biology of Poronia punctata (L.). Ann. Bot. xiv, p. 245. 



