ISO 



PYRENOMYCETES 



[CH. 



the formation of the sclerotium begins; chains of subaerial conidia may be 

 produced on conidiophores arranged in a coremium or fascicle of parallel 

 hyphae. This is the Isaria condition, and though there is little doubt that 

 it is a stage in the development of the Cordyccps, the ultimate proof by 

 culture has yet to be given. 



Fig. 1 10. a. Cord} 



nilitaris (I..) Link ; h. Cordyceps ophioglossoides (Ehrh.) Link; 

 after Tulasne. 



The mature sclerotium is a compact mass of interwoven hyphae whose 

 cells are rich in glycogen and oily matter. During its development the in- 

 ternal organs of the host are completely destroyed and replaced by the 

 mycelium, the skin alone remaining intact. From this mummified structure 

 one or more stromata arise, emerging between two segments of the skin, 

 usually near the head. The stroma is differentiated into an erect, sterile 

 stem, which may be simple or branched, and a globose or elongated, fleshy, 

 fertile portion, usually terminal on the stem and bearing the perithecia (fig. 

 in). It is pale or bright coloured; red in the best known British species, 

 C. tnilitaris ; and in other forms, purple, flesh-coloured, lemon-yellow or of 

 various shades of brown. 



