238 American Midland Naturalist Monograph No. 6 



or in forms up to 30 or 40 cm, bushy branched with erect branches or floating; 

 stem-leaves triangular ovate to lance-ovate and acuminate or lanceolate and 

 very slenderly acuminate when in water, often secund or falcate at ends of 

 branches, non-plicate, entire, the large inflated, thin-walled cells at the exca- 

 vated auricles decurrent, usually hyaline and reaching well towards the costa; 

 costa disappearing at or above the middle; m.edian; median leaf-cells linear- 

 flexuous (or wider in some varieties) ; branch-leaves smaller and narrower, and 

 often more falcate or even falcate-secund; seta about 2-4 cm long, rather slen- 

 der; capsule about 2-2.5 mm long, curved, cernuous; spores in late spring or 

 early summer; lid conic-apiculate; annulate. Not often found in fruit. 



Eurasia, northern Africa, New Zealand, and widely distributed in colder 

 and temperate parts of North America. 



Crawford Co.: Pymatuning Swamp, Linesville. O.E.J. Aug. 19, 1904 (figured). 

 Erie Co.: Numerous collections on Presque Isle by Nelle Ammons. Summer of 1935. 

 Lawrence Co.: In moist field with Gentiana crinita, Frew Mill Road, e. of New Castle. 

 C.M.B. Sept. 18, 1948. Warren Co.: Iron Spring bog, Columbus. C.M.B. Sept. 1, 

 1948. Westmoreland Co.: On rock in stream, Tannery Hollow, Chestnut Ridge. 

 C.M.B. Apr. 30, 1944. Elev. 1700 ft. 



5. Drepanocladus Kneiffii (Schimper) Warnstorf 



{Hypnum aduncum var. Kneiffii Schimper; Amblyslegium Kneiffii 

 Bryologia Europaea) 



Stems slender, long, flexuous, prostrate or ascending, more or less pinnate- 

 ly branched, the cross-section showing a central strand, but not a distinct corti- 

 cal layer of enlarged hyaline cells; leaves distant, broadly lanceolate to ovate- 

 oblong, costate to the middle at least, usually not secund nor falcate except 

 sometimes at the end of the branches, the acumen flat and entire, the lower 

 leaves usually shorter and wider; basal leaf-ceils much as in D. aduncus, the 

 alar large, inflated, and extending about half-way to the costa. Closely related 

 on the whole to D. aduncus, and by some bryologists regarded as merely a 

 variety of that species. 



Along streams and ditches, about as widely distributed as is D. aduncus. 



Butler Co.: In swamp among grasses, 1 m. west of West Liberty, June 28, 1941. 

 Charles M. Boardman. Erie Co.: Cranberry Pond, Presque Isle, Erie, July 30, 1935, 

 Nelle Ammons; on base of Alnus, May 8-9, 1906. O.E.J. 



6. Drepanocladus Sendtneri (Schimper) Warnstorf 

 {Hypnum Sendtneri Schimper) 



Rather strong plants in yellowish tufts, brownish below; stems 10-15 cm 

 long, erect, sparsely irregularly pinnately divided; leaves close, strongly falcate 

 or circinate, hooked at the ends of stems and branches, lanceolate to lance- 

 ovate, about 10-11 mm long, long-acuminate, entire, non-plicate, short-decur- 

 rent; costa strong and wide, extending into the leaf-tip; median leaf-cells 

 narrowly linear to somewhat oblong, about 6-10:1, basal larger, incrassate, the 

 alar forming a well-defined group of colored, incrassate, excavate, inflated 

 cells; dioicous; seta 3-4 cm, reddish, slender; capsule resembling that of 



