I] THE ALTERNATING GENERATIONS 25^^;^> " 



legists: always, however, with the willingness to apply any sound results 

 which they may obtain in helping to elucidate the problem of alternation 

 as it is seen in the Ferns and in other Archegoniate Plants. 



It will be manifest from the foregoing sketch that the sporophyte gene- 

 ration, being larger and more elaborate in structure than the gametophyte, 

 will be likely to yield more ample materials for comparison than the latter. 

 This is actually the case, and accordingly its details will be described first. 

 But none the less the features of the gametophyte must also be examined 

 in detail: for conclusions as to relationship and descent must be based upon 

 the whole sum of the characters which can be observed. 



BIBLIOGRAPHY FOR CHAPTER I 



1. Morrison. Historia Plantarum. Oxonii. 1699. First raised Fern-Plants from spores ^ 



2. Ehrhart. Beytrage. Hannover. 1788. Described the formation of the prothallus. 



3. Kaulfuss. Das Wesen der Farrenkrauter. Leipzig. 1827. First observed germina- 

 tion of the spores. He gives a full quotation, and extraction of the early literature. 



4. BiscHOFF. Handb. botan. Tenninologie. Niirnberg. 1842. Recognised the embryo 

 attached to the prothallus. 



5. Naegeli. Zeit. f. wiss. Bot. Zurich. 1844. Discovered the antheridia and sperma- 

 tozoids. 



6. SUxMINSKl. Z. Entwickelungsgesch. d. Farrenkrauter. Berlin. 1848. Ascertained 

 the nature of the archegonium, and its relation to the embryo. 



7. HOFMEiSTER. Vergleichende Untersuchungen. Leipzig. 1851. Gave the first com- 

 plete and comparative account of the life-history of a Fern. Historical review of 

 discovery of propagation of Ferns. Engl. Edn. Ray Soc. p. 257. 



8. Kny. Entw. d. Parkeriaceen. Nov. Act. Leopold. Bd. xxxvii, 4. Dresden. 1875. 

 Also Bot. Wandtafeln. Texte. xciii. Berlin. 1894. 



9. Engler & Prantl. Natiirl. Pflanzenfam. i, 4. Here the general literature is fully 

 quoted. 



10. Campbell. Mosses and Ferns. 2nd. Edn. London. 1905. Here the general litera- 

 ture is fully quoted. 



11. Bower. Origin of a Land Flora. London. 1908. 



12. Yamanouchi. Sporogenesis in Nephrodium. Bot. Gaz. Vol. xlv, 1908. Here the 

 cytological papers up to date are fully quoted. 



^ Valerius Cordus (1515—1544) of Wittenberg asserted that all kinds of Ferns reproduce by means 

 of dust that is developed on the backs of the leaves : but there appears to be no evidence how he 

 arrived at this conclusion. 



