Higher Cryptogamia and the Phaiierogamia. 443 



the archegonia themselves. In Riccia the antheridia and archs' 

 gonia originate very early, and the parenchyma of the frond 

 grows up around them as they advance in development ; in the 

 case of the antheridium its walls become adherent to the enve- 

 loping cells ; the archegonium remains free, and the apex of the 

 neck hangs out from the surface of the enlarged frond. 



Hofmeister states that he has several times seen spermatozoids 

 swimming about around the archegonia in longitudinal sections 

 of the involucres containing the archegonia of Jungermannia bicus- 

 pidata and J. divaricata, \^en these were brought quickly under 

 the microscope (PL XVII. A. fig. 1). Moreover in these species, 

 and also in /. bicrenata and scalaris, he found at the mouths of 

 archegonia which exhibited the first trace of the commencement 

 of the development of the fruit, more or less curled, colourless 

 filaments, which resembled the spermatozoids of each species in 

 size and aspect, but were motionless. 



Musci. 



The antheridia and archegonia of the Mosses essentially re- 

 semble those of the Hepaticse, exhibiting a germ-cell as d^free cell 

 produced in the base of the archegonium {or pistillidium) by free 

 cell-formation. The evidence of impregnation is altogether cir- 

 cumstantial as yet, but the existing facts and the analogies with 

 other families render it in the highest degree probable. 



In this family, as also in the Hepaticse, we have in the condi- 

 tions of the reproductive system a most remarkable set of.phae- 

 nomena, which, until the facts presently to be noticed were dis- 

 covered, seemed to have a close relation with those in the flower- 

 ing plants. The spores produce the leafy plant which bears ant he- 

 ridia and pistiiiidia, apparently the analogues of the stamens and 

 pistils of flowers ; but if we look a little more closely, we see that 

 the archegonia differ greatly from pistils (or ovaries), since they 

 do not contain ovules to be fertilized ; but a single cell in their 

 interior becomes developed into a complete fruit, often borne 

 upon a stalk, and in the Mosses of very complex structure, which 

 gives origin to a great number of new bodies, the spores repro- 

 ducing the leafy form. Thus, the pistillidium^ or as it is better 

 called, the archegonium, seems to bear a closer analogy to the 

 ovule than an ovaiy, and its free central cell to represent the em- 

 bryonal vesicle of the flowering plants. Thus Hofmeister, to 

 whom we owe most important researches on these subjects, com- 

 pares the cycle of development in Mosses and Hepaticai to the 

 '•^ alternation of generations" in the animal kingdom, and he 

 considers the spore-fruit or capsule a distinct body, related only 

 by descent to the leafy steniy being in fact the next generation of 

 the plant. A third generation is met with in the leafy-stemmed 



29* 



