620 MDSCI. (mosses.) 



1. D. loilgilOStie, Br. & Sch. Stem 1'- 3' high, with innovations from 

 near the apex ; leaves fragile, more or less falcate-secund, subulate-setaceous 

 from a dilated base ; costa broad, occupying all the upper portion of the leaf. — 

 On rocks, Alleghany Mountains. (Tab. 15.) (En.) 



13. TREMATODON, Rich. 



Calyptra cuculliform, inflated. Operculum subulate-rostrate. Capsule oval- 

 oblong, inclined, with a very long collum, annulate, long-pedicellate. Peristome 

 single : teeth ] 6, linear-lanceolate, perforated, or more or less cloven. Inflores- 

 cence dioecious : male flower gemmiform. — Short-stemmed, gregarious plants, 

 with long subulate-setaceous and continuously-costate leaves. (Name from 

 rprjpa, a perforation, and 68cov, a tooth.) (Tab. 15.) 



1. T. lOBBgicwllis, llich. Capsule with a narrow linear collum of twice 

 its length ; pedicel 1^'- 2' long, slender, flexuous, straw-colored. — Clayey and 

 sandy soil. New England to Florida, and Ohio, Cassels. (Tab. 15.) 



14. DICRANUI, Hedw. (Tab. 16.) 



Calyptra cuculliform. Operculum conic, long-subulate-rostrate. Capsule 

 oval, oblong or cylindrical, regular or somewhat gibbous, erect or cernuous, 

 long-pedicellate. Peristome single : teeth 1 6, linear-lanceolate, cloven half-way 

 or more into two unequal segments. Inflorescence monoecious or dioecious : 

 male flower gemmiform, terminal. — Perennial plants, growing on the ground 

 or on rocks ; stems from a few lines to several inches in height, fastigiately 

 branched and continued by innovations from near the apex ; leaves mostly 

 linear-lanceolate and lanceolate-subulate, continuously costate, often falcate- 

 secund, with a minute, compact, roundish areolation above. (Name from 

 dUpavos, forked, alluding to the teeth.) 



§ 1. CYNODONTIUM, Br. & Sch. — Leaves more or less papillose, crenulate-ser- 

 rate at the apex ; the areolation uniform at the base : calyptra infiated-cuculliform : 

 capsule mostly strumose and erect : monoecious. 



1. I>. gracilescens, Web. & Mohr., var. tencllum, Bryol. Europ. 

 Stems short, 4"- 10" high; leaves linear-lanceolate, scarcely papillose, the mar- 

 gins above plane, the costa vanishing at the apex ; capsule exannulate, oval, not 

 strumose, obsoletely striate. White Mts., New Hampshire, Oakes. (Eu.) 



2. I>. poSycsil'pMiii, Ehrh. Stems l'-2' high; leaves linear-lanceo- 

 late, variously curved, somewhat papillose on both surfaces, denticulate at the 

 apex and at the base ; capsule oval-oblong, erect, regular, or gibbous-inclined 

 and strumose, ribbed when dry ; annulus conspicuous. — Northern shore of Lake 

 Superior, Agassiz. (Eu.) 



3. !>. vSi'cns, Hedw., var. Walllenbergii, Bryol. Europ. More ro- 

 bust than the last; stems often 3' high; leaves spreading, flexuous, lanceolate- 

 subulate, smooth, denticulate at the apex, the costa nearly excurrent ; capsule 

 oblong, incurved, cernuous, prominently strumose, annulate. — Lake Superior, 

 Agassiz. (Eu.) 



