White : Tvlostomaceae of North America 435 



dium, which is tomentose on the lower half and not depressed, 

 and by its stem which is distinctly furrowed on the lower half." 



As this species was not seen the above original description is 

 quoted. The same is the case with the following description of 

 T. Wrightii, and the species which Morgan calls " T. Mtycniannm." 

 It has been thought best to include these descriptions in order 

 that our present knowledge of the group may be accessible in a 

 single paper. 



17. Tylostoma Wrightii Berk. Grevillea, 19: 95. 1891 



"Stem 6 cm. high, 4 mm. thick, hollow, equal, ochraceous, even, 

 glabrous ; peridium spherico-depressed, 2 cm. broad, minutely 

 umbonate, pale, ochraceous, glabrous, the wall of the umbo dis- 

 appears at maturit)' and forms a small circular stoma ; mass of 

 spores yellowish brown ; threads of capillitium h)-aline, thick- 

 walled, aseptate, equal, very long, branched, axis lunate, 5 fi in di- 

 ameter : spores glabrous, globose, pale yellow brown, minutely 

 warted, 5-6 />« in diameter. 



" On the ground. Rio Grande, North * Mexico (Wright). 

 Type in Herb. Berk. 



" Distinguished from Tiilostoma Meycnianuni in the entire mouth 

 and the hollow, even and not striated stem." 

 Tylostoma sp. (Described by Morgan, Jour. Cin. Soc. Nat. 



Hist. 12 : 163. //. 16. f. J, as T. Mcyeuiamnn Kl., but it is 



clearly distinct from that species, though it might possibly be 



referred to T. obcsiun C. & E.) 



" Peridium depressed, globose ; the cortex soon receding, leav- 

 ing a smooth whitish or yellowish surface to the submembrana- 

 ceous inner peridium, the apex plane with a lacerate mouth : 

 stipe long, thick, unequal, fusiform or tapering, nearly solid, sul- 

 cate : threads of the capillitium long, much thicker than the 

 spores, branched, hyaline : spores subglobose, even, pale brown, 

 4.5-5.5 mic. in diameter. 



"Growing in sandy soil. New Mexico, Wright; Colorado, 



Webber. Plant 2-4 inches in height, the peridium 3^'-i inch in 



diameter, the stipe about j^ of an inch in thickness at the thickest 



part. Specimens referred to T. Angolense W. & C. do not differ 



otherwise than in having the stipe thickest at the apex and taper- 



* Probably a misprint for New as Wright was not known to have collected across 

 the Rio Grande. 



