jiusci. (MOSSE&.) 615 



4. P. COh&rens, Hedw. Leaves oblong-lanceolate, strongly serrate; 

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

 tral Ohio. (Eu.) 



# # Plants without a confervoid thallus. Cdumella persistent. 



2. PHYSCOMITRELLA, Schimp. Caulescent : leaves loosely areolated : 

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

 with paraphyses globosely distended at the apex. (Closely allied to Aphanorhcg- 

 ma among Funarieae.) 



5. P. pateos, Hedw. Leaves subspatulate-laneeolate, serrate, costate 

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

 Ohio : rare. (Eu.) 



3. ACAtLON, Mull. Stemless, bulb-like: leaves broad-ovate or obovate, very 

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

 cealed by the 2 or 3 large subcucullate perichcetial leaves : calyptra minute, cam- 

 panulaie: inflorescence as in 1. 



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

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

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



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

 tlie perichajtial ones 2 : capsule erect ; pedicel straight. Moist ground. (Eu.) 



8. P. Schiniperianum, Sulliv. (Muse. Bor.-Amer., No. 26.) Re- 

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

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

 the costa which extends scarcely 4 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. 



(j 4. PHASCUM PROPER. Stems simple, or once or twice divided by innovations : 

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

 chlorophyll ose : calyptra cuculliform: capsule globular, acuminate. (Resembles 

 the Pottieae.) 



9. P. CUSpidatlllll, Schreb. Leaves elongated-lanceolate, cuspidate, 

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

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

 leaves. Old fields ; not uncommon. (Tab. 15.) (Eu.) 



45. PLEURlDIUM, Brid. Stems erect or decumbent: haves subulate, costate, 

 with a loose and oblong hexagonal reticulation : calyptia cuculliform or campanulate' 

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

 stem. 



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

 much longer, subulate from an oblong base ; costa excurrent, with the point 

 more or less serrulate ; capsule ovate, obtusely acuminate ; calyptra cuculliform ; 

 male flower gcmmiform, axillary. Old fields, &c. ; common. In American 

 forms the base of the leaves is usuallv more closelv areolated than in the Eu 



