54 BULLETIN 175, U. S. DEPARTMENT OF AGRICULTURE. 



ASCOMYCETES. 



The character peculiar to all fungi of the class known as Ascomycetes 

 is the production of spores in asci ; microscopic saclike bodies instead 

 of gills, tubes, teeth, or other specially modified structures. The 

 genera are subject to great variation in form, size, and consistency. 

 The plants may be spherical, elongated, expanded or cup shaped, 

 sessile or stipitate, microscopic or several inches in size, waxy or gela- 

 tinous, hard or soft, elastic or rigid. The genera described here may 

 be identified by the assistance of the accompanying key, which does 

 not require a consideration of microscopic characters. 



Key to Ascomycetes. 



Plants cup shaped to disk shaped, gelatinous, fleshy: 



Substipitate, closed at first, large, exterior rough, interior gelatinous- 

 pulpy Bulgaria. 



Plants stipitate, hymenophore clavate, globose or conical, deeply folded 

 and pitted Morchella. 



Plants stipitate, hymenophore irregular or lobed, with conspicuous brain- 

 like convolutions, hollow Gyromitra. 



Plants capitate, stem cylindrical or laterally compressed, gelatinous- 

 gristly, hymenophore undulated or even Leotia. 



Plants stipitate, urn shaped, leathery, blackish Urnula. 



BULGARIA. 



In the genus Bulgaria the plants are cup shaped, sessile, or sub- 

 stipitate and are either single or gregarious. They are of a pulpy 

 gelatinous consistency when fresh or in wet weather, but horny to 

 cartilaginous when dry. The two species most frequently encountered 

 by the collector are Bulgaria inquinans and B. rufa, both of which 

 grow on dead branches or fallen twigs. 



The cups of Bulgaria rufa are subturbinate, at first closed, later 

 concave, the margin wavy when old, hymenium light colored, plants 

 1 to 2 inches in diameter. Bulgaria inquinans may be distinguished 

 from B. rufa by the more uniform turbinate caps, dark hymenium, 

 and smaller size. (PL XXXVII, fig. 1.) 



MORCHELLA. 



The genus Morchella is very easily distinguished by the prominently 

 ridged and pitted hymenium (cap), which is hollow and continuous 

 with the cavity of the stem, to which it is adnate throughout its 

 length. The plants are stipitate, waxy, and brittle in consistency, 

 and the caps are conic or cylindrical to ovate. 



From early historic times the morels have been considered among 

 the choicest edible fungi. 



