30 ENGLISH BOTANY. 



linear, or curved, and sometimes naked, sometimes covered when 

 young by a membrane (induskan), sometimes enclosed in pouches 

 {involucres). Prothallium flat, green, resembling a frondose Liver- 

 wort, producing on its under side archegonia and antheridia, the 

 former producing a new plant when fertilised by the antherozoids of 

 the antheridia. 



According to Dr. TV. Gr. Farlow, in Pteris serrulata, the prothallium 

 was found in about 50 cases to produce a young plant, where no 

 traces of archegonia were seen. See ' Journ. Bot.' 1874, p. 185. 

 If this viviparous production of young plants be general, it may 

 account for the numerous curious facts that occur in the rearing of 



o 



Ferns from spores. 



Suborder I— SMUNDACE^l. 



Sporangia with an incomplete annulus on one side immediatelv 

 beneath the apex, opening by a longitudinal slit on the side opposite 

 to the incomplete annulus, and extending across the apex. 



GENUS I.—O S M U N D A. Linn. 



Caudex massive. Fronds tufted, coriaceous or herbaceous, pinnate 

 or bipinnate. Sporangia on a separate frond or on a portion of a frond 

 so contracted that it appears to be made up of clusters of sporangia 

 arranged in a compound spike, rarely with the barren portion inter- 

 rupted by a few fertile lateral pinnae. 



Name Osmunda, a Saxon name of the god Thor. But some authors derive it from 

 Osmund, a Saxon waterman, who is said to have hidden his wife and children among 

 the Royal Fern on an island in Loch Lomond, during an incursion of the Danes. 



SPECIES I.-O SMUNDA REGALIS. Linn. 

 Plate 1838. 

 Rabenh. Crypt. Vase. Exsicc. No. 10. 



Stipes nearly as long as the laminaB of the frond, rarely only 

 half as long. Barren frond subcoriaceous, pale green, glabrous when 

 mature, clothed with cinnamon-coloured arachnoid hairs when young, 

 which come off in floccose patches as the frond developes, oblong 

 or ovate-oblong, with a triangular apex, bipinnate ; ultimate pinnules 

 strap-shaped or oblong strap-shaped, obliquely truncate or sometimes 

 half-cordate at the base, tapering towards the subobtuse or subacute 



