288 American Midland Naturalist Monograph No. 6 



linear to elongate rhomboidal, alar quadrate, often numerous: seta 1-2 cm 

 high, smooth; capsule erect, symmetric, cylindric; operculum conic, apiculate 

 to short rostrate; annulus none; peristome cilia none or single and rudimen- 

 tary; spores ripe in autumn. 



This genus has been segregated from. Bracbythecium by Dr. Grout and 

 named in honor of E. B. Chamberlain (1878-1925), former secretary-treasurer 

 of the SuUivnnt Moss Society. Three species; two in our region. 



1. Chamberlainia cyrtophylla (Kindberg) Grout 



{Brachythecium cyrtophyllum Kindberg) 

 Plate LIII' 



Cespitose, lustrous, dark green: stem irregularly branching to sub-pinnate, 

 creeping, up to 4 to 6 cm long; stem-leaves broadly ovate, up to 1 mm long; 

 branch-leaves similar but narrower and smaller, lance-ovate to lanceolate, acute 

 to short-acuminate, 0.6-0.8 x 0.3 mm, rather close, loosely appressed when 

 dry, serrulate at least in the upper half, marginally reflexed at base, not plicate, 

 not decurrent, when moist more or less spreading; costa stout, reaching about 

 two-thirds the length of the leaf; median leaf-cells rhomboid-fusiform, about 

 4-8:1, the alar sub-quadrate, numerous, sub-inflated, somewhat chlorophyllose; 

 perichaetial leaves ecostate, half-sheathing: seta about 2-2.5 cm long, dextrorse 

 above, erect, flexuous; capsule erect, cylindric, sometimes slightly curved, from 

 1.5 to 3 mm long, castaneous, smooth; annulus none; peristome-teeth slender, 

 pale castaneous, confluent at base, hyaline and papillose above, the dorsal 

 lamellae closely cross-striolate below, the trabeculae close and strong; segm.ents 

 nrarly as Icn*] a3 the teeth, slender, pale yellowish, more or less carinately 

 split, the cilia rudimentary or none; basal membrane about one-fourth the 

 height of the teeth; lid high-conic, usually acutely apiculate; spores papillose, 

 brownish, medium- to thick-walled, .012-.016 mm, mature in autumn. Very 

 closely related to the following species, which it apparently replaces to the west 

 and northwest of our region. 



On roots and bases of trees and on old logs, in woods from our region 

 northwestward to Minnesota and Ontario, south to North Carolina. 



Uncommon in our region. Allegheny Co.: Fern Hollow, Pittsburgh, on old logs 

 in ravine, January 21, 1906 (figured), and March 8, 1908. O.E.J. McKean Co.: 

 Bradford. D.A.B. (Porter's Catalogue). 



2. Chamberlainia acuminata (Hedwig) Grout 



(Leskea acuminata Hedwig; Hypnum acuminatum Beauvois; 

 Brachythecium acuminatum Kindberg) 



Plate LIV 



Widely and somewhat densely cespitose, dark to yellowish-green, glossy: 

 stems slender, prostrate, up to 5 to 8 cm long, bearing rhizoids, at least near 

 the perichaetia, rather distantly and unequally branched, the branches two- 

 ranked, plumose to sub-julaceous, acute, not usually more than 1 cm long: 

 stem-leaves close, erect-spreading, lance-ovate to ovate, about 1-1.5 mm long, 



