PTERIDOPHYTA. 



707 



FJg. 400.— Various Ferns, 



oephrolepis Dufi. 2 Trichommies LyallU. 3 Sorus of the same fern, with cap-shaped investment seen in longitudinal 

 section. * Rhipidopteris iQeltata. ^ Polypodiura serpens. ^ Portion of frond of Gleichenia alpina. T Sckizceafistulosa. 

 ootryehium lanceolatum. 9 Under side of a fragment of the- frond of Gleichervia alpina; above the sporangia are 

 concealed by a tuft of scales, below they are exposed. 10 and n Fertile pinnule of Cyatkea, elegq,ns. 12 Longitudinal 

 BSctlon of a sorus of Cyathea. is Sporangium of Cyatkea. i* Sporangium of Polypodiuih. is Sporangium of Schizcea. 

 w Under side of the prothallium of A spLeniuin. 1, 2, 4^ s, 6^ 7, s natural size ; », 9. 10, ", ", is, u^ 15, " x 5 - 20. 



