532 



LIFE-HISTORIES 



Finally, in a considerable variet}- of ways means are provided for 

 scattering the spores as far as possible and under the most favorable 

 conditions for giving the new plants a good fair start. 



Bryophyta are disli)iguished by having archegonia on lobed or pseudo- 

 leafy gametophyles which bear sporophytes lacking true roots, stems, 

 and leaves. 



Fig. 357. — -Adder-tongue, A, and grape-fcrn, B {O phioglossum vulgatum 

 and Botrychium Lunaria, Adder-tongue Family, Ophioglossacew). 

 Sporophytes showing roots (w). stem (st), leaf-stalk (hs), point (x) at 

 which leaves branch to form a foliage-blade (h) and a spore-bearing 

 division (/). Two-thirds natural size. (Sachs.) — Not very common 

 but widely distributed in mostly open ground. 



192. The ferns (Class Filicinae). Our most primitive 

 ferns are represented by adder-tongues (Ophioglossum) and 

 grape-ferns (Botrychium, Fig. 357). 



Unfortunately their life-histories are not yet fully known owing 

 to peculiar difficulties in tracing the germination of the spores. 

 The gametophyte is sul)terrancan (Fig. 358) and at least when 

 mature it is saprophytic. Except for its lack of chlorophyll it is 

 not a little like the gametophyte of Riccia. The gametophyte of 



