and its relation to that in the Animal Kingdom, 351 



Leszczyc-Suminski* tlius represents the antheridia of Pteris ser- 

 rulata. Hofmeister observed sucli conditions only in the antheri- 

 dia of the proliferous shoots of abortive prothalliaf. ThuretJ 

 and Mercklin § regarded the centre of the antheridium as an in- 

 tercellular space; Schacht||, in agreement with his views of the 

 structure of the antheridia of Mosses, as a large cell, inside 

 which the swarming-filament cells originated in fours in mother- 

 cells. Henfreyll agrees with him in regard to the first point. 

 The shape of the spermatozoids and the mode of arrangement of 

 their cilia, first detected by Thuret and Suminski, are also stated 

 by Wigand ** to be very various. 



The archegonia, the discovery of which we owe to Leszczyc- 

 Suminski tt^ appear a little later, before the successive production 

 of antheridia is at an end, — ordinarily upon the same, but in a 

 few cases upon separate prothallia. They present themselves as 

 shortly cylindrical, ellipsoidal organs projecting from the pro- 

 thallium on the lower surface, and consist of four (8-10-jointed) 

 rows of cells surrounding a central canal. The canal is formed 

 either by the solution of the transverse walls of a fifth axial row 

 of cells, or by the separation of the four rows at their common 

 commissure. Both modes of formation occur in difierent arche- 

 gonia of the same species, even of the same prothalliumjf. Ac- 

 cording to Mettenius§§, the lower part of the canal is formed as 

 an intercellular space above the central cell of the archegonium 

 (called by Mettenius the germinal vesicle) before the longitu- 

 dinal growth of the cylindrical neck of the archegonium is com- 

 pleted. This canal leads at the bottom to a cell, distinguished 

 by its magnitude, seated at the base of the archegonium — the 

 central cell of the archegonium. In this, as in the Mosses, be- 

 fore the opening of the canal externally, a free cell (germinal 

 vesicle), a daughter-cell, is formed around a new secondary cell- 

 nucleus HH, constituting the foundation of the new plant l[Tf. 



* Zur Entwickl. der Farrnkr. Berhn, 1848. 



t Vergleich. Untersuch. &c. p. 84. 



X Sur les Antherid. des Fougeres. Ann. des Sc. nat. 3 ser. xi. p. 5 (1849). 



§ Beobacht. an dem Prothall. der Farrnkr. Petersburg, 1850. 



II Pflanzenzelle. Berlin, 1852, p. 114; and Beitrage zur Entwickl. der 

 Farmkrauter, ^Linnaea/ xxii. p. 753 (1849). 



IF On the Dev. of Ferns from their Spores. Trans. Linn. Soe. London^ 

 xxi. p. 121 (read June 15 and Nov. 2 & 16, 1852). 



** Op. pit. p. 46. ft Op. cit. 



XX The Ferns thus form, in reference to the construction of the arche- 

 gonia, the connecting link between the Mosses on one side and the Rhizo- 

 carpese and Lycopodiaceae on the other. Hofmeister, Vergl. Untersuch. 

 p. 81. §§ Beitr. z. Botanik, Heft i. p. 18. Heidelberg, 1850. 



nil Fic?e Hofmeister, Ueb. Befrucht. der Farrnkr. 'Flora/ 1854. (Ann. 

 Nat. Hist. 2 ser. xiv. p. 272.) 



nil As to the presence of this cell at the epoch before the archegonium 



