REJUVENESCENCE IN NATURE. 309 



flower-bud detached from the mother-plant. On such a 

 theory, the new individual cycle of development would 

 not begin with the spore, but with the central cell at the 

 base of the archegonium.* Applying this view to the 

 Moss, the first (lowest) stage in the cycle of its indi- 

 vidual life would be the formation of the sporangium, 

 the second stage that of the confervoid prothallium, the 

 third that of the leafy stem, which would finally bear, as 

 the term of the development, the impregnation-organs, 

 antheridia and archegonia. The more minute investi- 

 gation of the still imperfectly ascertained processes of 

 impregnation in the Rhizocarpese and Lycopodiacese, as 

 also those of the Gymnosperms, (Cycadeae and Coniferse,) 

 aberrant among the Phaneroganiia, and perhaps having 

 an affinity to the higher Cryptogamia, will certainly 

 enable us to place the strange conditions in the repro- 

 duction of the Mosses and Ferns in clearer connection 

 with the reproduction of the Phanerogamia, while the 

 investigation of the Characeae and Florideae promises a 

 new point of attachment for the lower department of the 

 Cryptogamia.t 



That an actual impregnation does occur in the Mosses 

 and Ferns is indicated not merely by the well-known 

 experience of bryologists on the dependence of the fructi- 

 fication of dioecious Mosses on the social growth of the 

 two sexes, j but also the occurrence of hybrids, which 

 were known in the Ferns even before the discovery of the 



* According to Suminski's here certainly incorrect representation, the 

 embryo of the new individual is formed in the central cell of the archegonium, 

 through the penetration of the tail of a spermatozoid into it. 



f (The above was printed in 1850 ; the speculation then put forth has been 

 realized to an extent scarcely to have been expected so soon ; the researches 

 of Mettenius, Nageli, and above all Hofmeister, have carried on this subject 

 almost to completion in its main features in the higher Cryptogamia ; the 

 lower Cryptogamia, (Thallophytes,) still require extensive investigation. For 

 the facts, as also the literature, see the ' Report on the Reproduction of the 

 Higher Cryptogamia,' by the present translator, in the 'Annals of Nat. 

 Hist., 2 ser., vol. ix, p. 441. A. H.) 



$ See Schimper, 'Recherch. sur les Mousses,' p. 55. 



