*** Perithecia cespitose (or sometimes simply 

 gregarious,) connected at base by a more 

 or less distinct stromatic layer. - Cucurbitarieae. 

 B. Perithecia included in a stroma {Compound Sphderiae.) 



Stroma effused, pdlvinate or tuberculiform; perithecia ■ 

 buried in the stroma, their ostiola (typically) 

 convergent and erumpent in a central fascicle. Valseae. 



Stroma valsoid, pulvinate, conical or hemispherical, 

 often inconspicuous or wanting, accompanied 

 mostly by a conidial stroma, Melanconideae. 



Stroma various; pulvinate, tuberculiform, etc., 

 erumpent or superficial. Spermatia and 

 stylospores produced in cavities within the 

 perithecial stroma. (1.) Melogrammeae. 



Stroma effused, scutellate, pulvinate or tuberculiform. 

 Perithecia monostichous or polystichous, with 

 their ostiola separately erumpent. (2.) Diatrypeae. 



Stroma various; upright, dendroid, pulvinate, or 



globose; mostly carbonaceous and superficial, 



black, or becoming black. Sporidia, brown or 



black. (3.) Xyl^rieae. 



SnnORDER DOTHIDEACEAE. 



Stroma pulvinate or effused, coriaceous, or subcarbon- 

 aceous; perithecia reduced to mere cells or 

 cavities in the stroma. Sporidia hyaline, 

 yellowish or brown Dothideaceae- 



SUBORDER HYSTERIACEAE. 



Stroma none. Perithecia simple, erumpent-superficial, 

 oblong or linear, membranaceous, coriaceous or 

 carbonaceous, becoming black, opening by a 

 narrow, longitudinal cleft. -, ITysteriaceae.j- 



I. Includes Botryosphaeria, Myrmaecium, Endoikia, Metogramma, 

 and Valsaria. (pp. 546 564,) 



^. Includes Diatrype, Anthostoma &nd Diatrypella (pp. 565-595.) 



The diagnoses of these two families were omitted in their proper place 

 in the N. Am. Pyrenomycetes. 



3 This family should precede Dothideaceae in the systematic arrangement, 



fThis suborder does not properly belong to the Pyrenomycetts but is included here for 

 the present as a matter of convenience. 



