42 TORTULACEAE 



crisped when dry and strongly papillose on both sides; very 

 strongly resembling sterile Weisia viridnla. 



A. Sullivantii (Schimp.) Hampe. Common in old fields, 

 gardens and meadows. A. crispum and A. nitidulum have been 

 frequently reported but my observations incline me to the 

 belief that we have but one species. For a full discussion of 

 the matter see Mosses with Hand-lens and Microscope, pp. 

 137-139. The leaves are much like those of the next. Autumn 

 to spring. 



WEISIA Hedw. 



Small mosses growing in tufts or mats on soil, especially 

 rather dry sandy soil in our species, freely branching; upper 

 leaves usually much larger than the lower, erect-spreading, 

 strongly crispate when dry, elongated-lanceolate with the costa 

 usually excurrent into a short point; basal cells rectangular and 

 hyaline, the upper small roundish and thickly papillose with 

 small papillae; capsule well exserted on a seta of moderate 

 length, usually erect and symmetric, ovoid, plicate when dry 

 and empty; peristome rudimentary, teeth short, sometimes 

 perforate or somewhat divided, rarely almost lacking. 



W. viridula (L.) Hedw. Very common in rather dry soil and 

 occasionally growing in more moist situations. It is exceedingly 

 variable in its peristome and its size. It may usually be dis- 

 tinguished from Astomum when sterile by its larger size and 

 longer leaves. 



Var. gymnostomoides (Brid.) Muell. "Rocky ground, 

 Palisades of N. J.," Muse. App. 63. 



GYMNOSTOMUM Hedw. 



Plants dioicous, densely caespitose, ferruginous below, grow- 

 ing mostly in limestone regions. Leaves small, gradually in- 

 creasing in size upwards, tufted at apex, scarcely crisped when 

 dry, but somewhat twisted and appressed, linear-lanceolate to 

 narrowly linear, costa and lamina papillose on both sides with 

 rather low papillae; lower cells rectangular, upper roundish 

 quadrate; capsule long-exserted, erect, symmetric, ovoid to 

 oblong-ovoid, smooth and glossy when first ripe; peristome 



