CEYPTOMYCES. 73 



Readily distinguished by the narrowly clavate spores and 

 by the host. 



Specimens examined in Scler. Suec., 133, and Rehm, Asc., 

 n. 468. 



Doubtful species. 



Rhytisma urticae. Fries, Syst. Myc., ii. p. 570 ; Cke., 

 Hdbk., p. 756; Rehm, Krypt. Fl., p. 86; Sacc., Syll., n. 

 3092. 



Stroma forming an effused shining black crust of variable 

 form, and often quite encircling the stem, 16 cm. long; 

 internally grey, and composed of interwoven hyphae ; 

 ascophores gregarious or somewhat scattered, slightly 

 elevated, elongated up to 1*5 mm., splitting and exposing 

 the grey disc ; asci clavate, 8-spored ; spores irregularly 

 biseviate, cylindrical, both ends rather obtuse, hyaline, 

 continuous, straight or very slightly curved ; 15-30 X 4-5 p; 

 paraphyses slender, hyaline. 



Xyloma urticae, Wallr., Fl. Crypt. Germ., p. 209. 



On decaying nettle stems. 



Rehm says in his diagnosis of the present species, " spores 

 l(-2?) celled." I have not met with septate spores in the 

 specimens contained in any of the exsiccati quoted by 

 him, and I have carefully examined each one. According 

 to Fuckel Syrnb. Myc., Suppl. ii., p. 52 the stylospores of 

 the present species are elongated, both ends narrowed, 

 often crooked, continuous, 24 x 5-6 /x., and are mature in 

 February and March. 



Differs from the typical structure of the genus in the 

 biseriate spores. 



Specimen examined from Cooke's Fung., Brit, exs., n. 

 392. 



CRYPTOMYCES. Greville. (figs. 4-6, p. 91.) 



Ascophores innate, gregarious, springing from a broadly 

 effused white stroma, depressed, covered with the bark of 

 the host, which remains connate with the black, parenchy- 

 matous excipulum, the whole forming broadly extending, 

 blistered or bullate, black, carbonaceous patches, finally 



