ON THE HIGHER ORYPTOGAMOUS PLANTS. 10? 



the same way as those bodies do upon the pro-embryos of the said families. 

 It would occupy too much space to enter into a minute detail of tlie various 

 conditions that are met with. It is sufficient to say that in all cases the 

 physiological stages are analogous to those of the Mosses ; since the pistil- 

 lidia produced upon the fronds or leaf-bearing stems developed directly from 

 the spores, go on to produce a sporangium alone, in which the new spores 

 are developed, without the intervention of the stage of existence presented 

 by the pro-embryo of the Ferns and Equisetacas, where the pistillidia and 

 anlheridia occur upon a temporary frond, and the former give origin to the 

 regular stem and leaves of the plant. 



Ferns. — This class formed for a long time the great stumbling-block to 

 those who sought to demonstrate the existence of sexuality in the Crypto- 

 gamous plants. The young capsules were generally considered to be the 

 analogues of the pistillidia of the Mosses, and the young abortive capsules 

 which frequently occur among the fertile ones were supposed by some 

 authors to represent the antheridia. Mr. Griffith*, sliorlly before his death, 

 noticed a structure which he was inclined to regard as the analogue of the 

 antheridium in certain of the ramenta upon the petioles. 



In the year 1844, Prof. Nagelif published an account of his observations 

 on the germination of certain Ferns, and announced the discovery of moving 

 spiral filaments closely resembling those of the Charag, on certain cellular 

 structures developed upon the pro-embryo or cellular body first produced by 

 the spore. It is not worth while to enter into an analysis of his observations, 

 as they have since been clearly shown to have been very imperiect ; it is 

 sufficient to state that he only described one kind of organ, and from his de- 

 scription it is evident that he confounded the two kinds since discovered, re- 

 garding them as different stages of one structure. The announcement of this 

 discovery seemed to destroy all grounds for the assumption of distinct sexes, 

 not only in the Ferns but -in the other Cryptogams, since it was argued that 

 tl)e existence of these cellular organs, producing moving spiral filaments, the 

 so-called spermatozoa, upon the germinating fronds, proved that they were 

 not to be regarded as in any way connected with the reproductive processes. 



But an essay published by the Count SuminskiJ in 1848 totally changed 

 the face of the question, and opened a wide field for speculation and investi- 

 gation on this subject, just as it was beginning to fall into disfavour. Count 

 Suminski's paper gives a minute history of the course of development of the 

 Ferns from the germination of the spore to the production of the regular 

 fronds, and he found this development to exhibit phaenomena as curious as 

 they were unexpected. The cellular organs seen by Nageli were shown to 

 be of two perfectly distinct kinds, and moreover to present characters which 

 gave great plausibility to the hypothesis that they represented reproductive 

 organs ; moreover, this author expressly stated that he had obtained abso- 

 lute proof of sexuality by observing an actual process of fertilization to take 

 place in the so-called ovules, through the agency of the spiral filaments or 

 spermatozoa. 



The main points of his paper may be briefly summed up as follows. The 

 Fern spore at first produces a filamentous process, in the end of which cell- 

 development goes on until it is converted into a Marchantia-like frond of 

 stmall size and exceedingly delicate texture, possessing hair-like radicle hairs 

 on its under side. On this under side become developed, in variable num- 



* Posthumous Papers, Journal of Travels, 444. 



t Zeitschrift fiir Wiss. Botanik, Heft 1. Zurich, 1844. 



\ gvjT Eiitwiclie|ungsgescluchte ^pr Farrenkrauter. Berlin, 1848. 



