Musci. (mosses.) (15) 615 



4. P. coh^erens, Hedw. Leaves oblong-lanceolate, strongly serrate; 

 costa vanishing below the apex ; capsule brownish-purple. — River-banks, Cen- 

 tral Ohio. (Eu.) 



* # Plants without a confervoid tTiallus. Columella persistent. 



§ 2. PHTSC0MITRI:LLA, Schimp. — Caulescent : leaves loosely areolated : 

 calyptra campanulate-conic : capsule globose, apiculate : antheridia naked, axillary, 

 with paraphyses glohosely distended at the apex. (Closely allied to Aphanorheg- 

 ma among Funariese.) 



5. P. pa,teiis, Hedw. Leaves subspatulate-lanceolate, serrate, costate 

 nearly to the apex; capsule sometimes exserted. — Moist clayey soil, Central 

 Ohio: rare. (Eu.) 



§ 3. ACAULON, Mull. — Stemless, bulb-like : leaves broad-ovate or obovate, very 

 concave, recurved at the apex, with a lax areolatian : capsule globose, entirely con- 

 cealed by the 2 or Z large subcucullate perichcetial leaves : calyptra minute, cam- 

 panulate : inflorescence as in ^ 1 . 



6. P. tflquetrum, Spruce. Leaves 3-ranked, carinate-concave, shortly 

 cuspidate by the continuous excurrent costa, the perichsetial ones 3 and larger ; 

 capsule horizontal, with a curved pedicel. — On dry soil; rare. (Eu.) 



7. P. inuticum, Schreb. Size of the last ; leaves not carinate, costate, 

 the perichoBtial ones 2 ; capsule erect ; pedicel straight. — Moist ground. (Eu.) 



8. P. IScMmperiaiiniii; SuUiv. (Muse. Bor.-Amer., No. 26.) Ee- 

 sembles the last two species, but the perichsetial leaves near the apex are papil- 

 lose on both surfaces, erose-dentate on the reciirved margins, and cuspidate by 

 the costa which extends scarcely \ of the way towards their base, the other leaves 

 without any trace of a costa ; capsule, pedicel, and calyptra as in No. 7. — San 

 Marcos, Texas, Wright. 



§ 4. PHASCUM Peopee. — Stems simple, or once or twice divided by innovations : 

 leaves costate; areolation below large, loose, oblong, above minute, subquadrate, 

 chlorophyllose ; calyptra cucullifl>rm : capsule globular, acuminate. — (Resembles 

 the Pottiese.) 



9. P. Clispidatlllll; Schreb. Leaves elongated-lanceolate, cuspidate, 

 more or less papillose on the back near the apex; costa excurrent; capsule 

 immersed or exserted ; antheridia mostly naked in the axils of the perichtetial 

 leaves. — Old fields ; not uncommon. (Tab. L) (Eu.) 



§ 5. PLEURf DIUM, Brid. — Stems erect or decumbent : leaves subulate, costate, 

 with a loose and oblong hexagonal reticulation : calyptra cuculliform or campanulate- 

 conic : capsule globular or ovate ; sometimes becoming lateral by innovations of the 

 stem. 



10. P. alternifolinni, Brid. Lower leaves ovate-lanceolate, the upper 

 much longer, subulate from an oblong base ; costa excui-rent, with the point 

 more or less sen-ulate ; capsule ovate, obtusely acuminate ; calyptra cucuUifoi-m ; 

 male flower gemmiform, axUlary. — Old fields, &c. ; common. — In American 

 forms the base of the leaves is usually more closely areolated than in the Eu- 



