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Farmer and Dig by. — Studies in Apospory and 
nected with the former that it occurs as an intercalated phase somewhere 
in the life-cell cycle of every animal and plant that reproduces sexually. 
But the proper bearings, if any, of these cyclically recurring events upon 
morphological conceptions, e. g. that of alternation of generations, are 
still obscure, because we are at present in possession of so little of the 
evidence. 
Considerations of this kind have strongly attracted us to the study 
of apospory and apogamy in Ferns, and especially towards the cytological 
aspects of the problem. 1 Many new facts have in the meantime been 
elucidated by workers in connexion with other groups of plants, but it 
seemed especially desirable that the Ferns, owing to the important position 
which the independence of the gametophyte and sporophyte generations 
respectively assures to them, should be closely investigated. 
Since the discovery of apogamy by Farlow in 1874 and by De Bary 
in 1878, in various species of Ferns, our knowledge of the phenomena 
both of apogamy and of apospory has been greatly extended by the 
investigations of Druery 2 Bower 3 Lang 4 and others, who have not 
only increased the number of species in which the processes are known 
to occur, but have contributed much to elucidate the structural features 
involved. 
The present paper will only deal with the results of our studies on the 
following plants, Lastrea pseudo-mas vars. polydactyla , Wills ; polydactyla , 
Dadds ; and cristata apospora , Druery. Athyrium Filix-foemina vars. 
clarissima , Jones; clarissima , Bolton; and unco-glonieratum , Stansfield. 
Scolopendrium vidgare var. crispuin Drummondae. 
We desire to express our indebtedness to Dr. Lang for apogamous 
prothallia of Lastrea ps.-m. polydactyla, Wills; to Prof. Bower for a fine 
plant of Athyrium Filix-foemina var. clarissima , Jones ; and to Mr. Druery, 
who with unfailing generosity has supplied us with examples of all the 
other Ferns, and has assisted us in other ways from his fine collection 
of living plants. The actual cultivation of the material has been carried 
on at the Chelsea Physic Garden under the care of the curator, Mr. Hales. 
probably always occurs in the first or heterotvpe division. The premeiotic number of chromosomes 
is that present between sexual fusion, resulting in the embryo, and the meiotic divisions in (the 
spore-mother- cells of) that embryo after it has become adult. Post-meiotic cells are those that 
intervene between meiosis and sexual fusion, thus they include all the normal gametophytic nuclei. 
1 Cf. Farmer, Moore and Digby, On the Cytology of Apogamy and Apospory, I. Preliminary 
note on Apogamy, Proc. Roy. Soc,, vol. lxxi. Also Digby, Miss L- II. Preliminary note on 
Apospory. Ibid. vol. lxxvi. 
2 Cf. Druery, T- C., various papers in the Journal of the Linnean Society from 1884 to 1894, 
and elsewhere ; also his Book of British Ferns, London. 
3 Bower, F. O., On Apospory and Allied Phenomena. Trans. Lin, Soc., 2nd ser., vol. ii, 1887. 
Also, On some Normal and Abnormal Developments of the Oophyte in Trichomanes. Annals of 
Botany, vol, i ; and other papers. 
4 Lang, W. H., On Apogamy and the Development of Sporangia upon Fern Prothalli. Phil. 
Trans. Roy. Soc., vol. 190 (1898), 
