242 American Midland Naturalist Monograph No. 6 



3. Calliergon stramineum (Dickson; Bridel) Kindberg 



(Hypnum stramineum Dickson) 



Very slender yellowish-green mosses of cold bogs, erect or ascending in soft 

 tufts; stems up to 20 cm long; stem-leaves oblong-lingulate, concave, cucullate 

 at apex, entire, up to 2 x 1 mm; alar cells abruptly enlarged forming decurrent 

 auricles, apical tending to rounded-quadrate; costate to about % length of leaf. 

 Northern Eurasia and from Arctic America south to New Jersey and eastern 

 Pennsylvania (Pocono Mts.). Not reported from our region. 



4. Calliergon trifarium (Weber and Mohr) Kindberg 



(Hypnum trifarium Weber and Mohr) 



When dry, in rather stiff and lustrous tufts, yellowish-green above to brown 

 below; stems and branches julaceous both wet and dry; stem-leaves appressed, 

 concave, broadly ovate to almost orbicular, obtuse, entire, scarcely decurrent; 

 costa thin, vanishing at about the middle or little above; median leaf-cells 

 linear-flexuous, shorter but scarcely wider above, the basal and alar thick- 

 walled, shorter and broader, but not much different. Cold bogs, especially if 

 calcareous, Eurasia and from Arctic America, south to Ohio and Connecticut. 

 Not yet found in our region. 



10. Calliergonella Loeske 



(Acrocladium Mitten, in part) 



Autoicous or dioicous: robust, rather stiffly but loosely cespitose, lustrous, 

 green to yellowish or brownish; stems long, densely foliate, the apex of the 

 shoots rigid and acuminate by reason of the convolute apical leaves, the stems 

 erect, not bearing rhizoids, or procumbent, here and there with fascicles of 

 rhizoids, irregularly branched; stem-leaves appressed, smooth, drying somewhat 

 imbricate, when damp erect-spreading, concave, often cucullate. from a narrow 

 and sub-decurrent base broadly oblong-ovate, obtuse, rarely apiculate, entire, 

 the margin apically more or less involute; branch-leaves smaller and propor- 

 tionally narrower than stem-leaves; costa short and double or none; leaf-cells 

 narrowly verm.icular, smooth, wider and porose towards the base, in the exca- 

 vate alar portions lax,, oval-4-6-sided, hyaline, thin-v/illed, forming a d'stinct 

 auricular group; inner perichactial leaves erect, entire: seta 3-7 cm high, 

 twisted, reddish; capsule horizontal from an erect collum, oblong to cylindric, 

 drying arcuate and dorsally gibbous, smooth or plicate, little narrowed below 

 the mouth; peristome normally hypnoid with appendiculate cilia; lid convex- 

 conic. 



As here recognized the genus consists of one species. 



1. Calliergonella cuspidata [Linnaeus] Loeske 



(Hypnum cuspidatum Linnaeus; H. flexile Bridel; Calliergon cuspidatum 

 Kindberg; Acrocladium cuspidatum Lindberg) 



Plate XLIV 

 Tall and moderately robust with characters mainly as outlined for the 



