XL] GROUPING OF THE WOODSIEAE 119 



and Nephrodioid prothallus, may be held as the most advanced of the three. 

 The genera thus placed suggest that an evolutionary line has moved from a 

 Gleichenioid source, through types like the Cyatheaceae with a radial sorus, 

 towards t}'pes like those found in the Dryopteroid Ferns with a lop-sided 

 sorus, though none of the living genera may themselves have been the actual 

 phyletic links. Hypoderris, with its reticulate venation, is clearly a specialised 

 collateral type: but it may very well be held as indicating a line leading in 

 the direction of certain types of Dryopteroids and possibly by complete 

 abortion of the basal indusium may have foreshadowed some Ferns that 

 have been included under the comprehensive title oi Polypodhcm, 



WOODSIEAE 



A. Sorus gradate, 



(i) Woodsia R. Brown, 1810 ... ... ... 25 species. 



B. Sorus mixed. 



(2) Diacalpc 'QXwTiXQ, 1828 ... ... ... i species. 



(3) Peranema Don, 1825 ... ... ... i species. 



C. Venation reticulate. 



(4) Hypodcrj'is R. Brown, 1830 ... ... ... 3 species. 



Genera incertae sedis 



(5) CystopterisV)Qxv\-\?Lx6\,\'$>o6 ... ... ... 13 species. 



(6) Acropliorus Presl, 1836 ... ... ... i species. 



BIBLIOGRAPHY FOR CHAPTER XL 



654. R. Brown. Prodromus Florae Novae Hollandiae. 1810. 



655. R. Brown. On Woodsia^ Trans. Linn. Soc. ll, p. 170. 18 12. 



656. R. Brown. Notes and observations on Indian Plants, Miscellaneous Works, ll, 

 p. 543. 1830. 



657. Sir W. Hooker. Genera Filicum, Tab. cxix, etc. 1842. 



658. Mettenius. Filices Horti Lipsiensis, p. no. Leipzig. 1-856. 



659. DiELS. Engler u. Prantl, Nat. Pflanzenfam. i, 4, p. 159. 



660. Christ. Farnkrauter, pp. 282, 323. 1897. 



661. Heim. Flora, Bd. Lxxxii, p. 355. 1896. 



662. SCHLUMBERGER. Flora, Bd. cil, p. 383. 191 1. 



663. R. C. Davie. Ann. of Bot. xxvi, p. 245, 1912, where the literature is fully quoted. 



664. R. C. Davie. Ann. of Bot. xxx, p. loi. 1916. 



665. Bower. Ann. of Bot. xxvi, 1912; Studies II, p. 306. 



666. Von Goebel. Organographie, Bd. ii, p. 1148, etc. 1918. 



