SPORES AND THALLIDIA. 



11 



Fig. 189. Ferns. 



Nephrolcpis Duffi. a Trichomanes Lyelli. 8 Sorus of the same Fern with cup-shaped investment seen in longitudinal section. 

 * RMpidopteris peltata. 6 Polypodium serpens. 6 Pinna of Gleichenia alpina. 1 Schizcea fistulosa. 8 Botrychium lanceo- 

 laturn. Under side of a pinna of Gleichenia alpina ; in the two upper cavities the sporangia are covered by leaflets, in 

 the under ones they are exposed. 10 , i 1 Pinna of Cyathea elegans. * 2 Longitudinal section through a Sorus and Cup of 

 Cyathea. is Sporangium of Cyathea. 1* Sporangium of Polypodium. 1* Sporangium of Schizcea. " Under side of the 

 Pru thallium of Spleen wort. l , 2 , *, 6 , 6 , 7 , 8 natural size ; s, 9 , 10. 11, 12. is. u > i5 > ie magnified from 5 to 20 times. 



