296 



Mycological Bulletin No. 74 



[Vol. V. 



Mouth definite, tithiihir, round, naked, more or less protruding. 



Spores smooth Group 1. 



Spores not smooth. 



Cortex granular or tubercular or scaly Group 2. 



Cortex not granular or tubercular or scaly. 



Stipe with strong scales, [No American Species] . .Group 3. 

 Stipe without strong scales. 



P-eridium uncolored Group 4. 



Peridium colored Group 5. 



Mouth definite, naked, elongated, sonietinics sez'eral on same perid- 



nan Group 6. 



Month with an indefinite, torn aperture, not surrounded with, a 



fibrillose layer, [No American Species] Group 7. 



- Mouth surrounded zvitli a fibrillose layer. 



Spores smooth Group S. 



Spores granular Group fl 



Mouth "fimbriate" [No American Species] Group 10 



GROUP 1. 



TYLOSTOMA OCCIDENTALE.— Peridium white, with a small, 

 tubular, circular, protruding mouth. Cortex adhermg, separating imper- 

 fectly, largely adhering in patches to the peridium, not sirongly thickened 

 at the base. Stem pale, not scaly, strongly longitudinally striate, white 

 internally, hollow with a central fibril. Capillitium slightly colored, with 

 plane or oblique unthickened septa. Spores 4-.5 mic. almost smooth. 



This species is very close to Tylostoma albicans, but on comparison is 

 quite different. The peridium is much whiter, the stem strongly striate, 

 the spores smoother. Specimen from the state of Washington. 



Fig. 221. — Ty-i.()S'-io-ma ()c-ci-i)en-i a'-i e. (C. (j. lAoyd). 



