348 



COMPARATIVE MORPHOLOGY OF FUNGI 



will not be destroyed before spore formation, the periphery of the pileus 

 grows into the stipe below. Gyromitra infula belongs to this type (Fig. 

 231). The pileus lobes have coalesced and grown to the stipe, forming a 

 hollow, campanulate structure with the hymenium outside. The surface 

 growth of the hymenium continues even after this coalescence; being 

 fixed below, however, the hymenium can no longer follow it and arches 

 up in folds and pads. 



From Gyromitra infula it is only a short 

 step to Verpa and Morchella. In Verpa (Fig. 

 232) the pileus forms regular folds; it remains 

 free at the bottom, however, so that it hangs 

 from the top of the stipe like the pileus of a 

 Coprinus. In the edible Gyromitra esculenta, 



a b c 



Fig. 232. — Verpa bohcmica. a, b. Immature fructifications; c. Mature fructification. 



(After Falck, 1916.) 



it is still free and entirely smooth in the young specimens just emerging 

 from the soil; later, as in H. lacunosa, it coalesces with the stipe and then 

 lies in deep, tortuous, forking and intersecting folds. 



In the highest forms of the family, the morels, these folds are still 

 more marked, they gradually become arranged with their interiors 

 together and develop to knife-like ridges and groinings. The backs of 

 these groins are sterile, so that the fertile layers are divided into numerous 

 lacunose hymenia. In the simplest species, as Morchella rimosipes (Fig. 

 233), the lattices run chiefly meridionally and are comparatively little 

 indented. In the higher forms, as Morchella esculenta, the hymenial 



