66 



Leaves and amphigastria two lobed, or with hairy teeth. 



Leaves with hairy teeth, or deeply two or three cleft, the divisions 



having long, acute points. PTILIDIAC: 

 Leaves with two unequal lobes. 



Perianth flattened, two lipped. Elaters with two spiral fibres. 



MODOTHECACEJ:. 



Perianth regular or nearly so, round or angular divisions sharp 

 pointed. Elaters with a single spiral thread. FRULLANIACE.E. 



151. Divisions of the frond lobes resembling leaves. Perianth partly 



joined to the many-leaved involucrum. FOSSOMBRONIACE .>:. 

 Divisions of the frond not leaf-like. 



Lobes of the frond without ribs. Fruit inserted in the lower face 



of the frond. ANEURACE^. 

 Lobes of the frond with plain ribs. 



Fruit inserted on the lower face and on the ribs of the frond. 

 Frond with elongated, forked divisions. Perianth none. 



METZGERIACE^E. 

 Fruit inserted on the upper face of the frond. 



Perianth tubular. BLYTTIACE^B. 

 Perianth none. PELLIACE/E. 



152. Capsules arranged on a common, columnar receptacle, two 

 valved. Perianth none. Spores with imperfect elaters or none. 



ANTHOCERACE.E. 



Capsules arranged under an enlarged, hat-like, common receptacle, 

 which is supported by a peduncle. Capsule opening by a single 

 slit. Spores with elaters. 153 

 Capsules sessile or immersed in the frond. Spores without elaters. 



Frond with a membranous wing and spirally undulated, ribbed. 



DORICEACE^. 

 Frond more or less flattened, without a -membranous wing. 



Fruit sessile on the upper face of the frond. CORSINIACE.K. 

 Fruit immersed in the frond. Ri< i . 



