SEXUALITY IN THE LOWER CRTPTOGAMIA. 77 



not always, enclosed in special cells or conceptacles. M, Pringsheim 

 long since suggested* that these conceptacular spores, called cystocarps 

 by Nageli, are either true female sexual organs, or that they produce, 

 like the spores of ferns, an organ which performs in some way the 

 female sexual functions. It would seem, however, that he has since 

 seen reasons for changing this opinion, for in the Eotanische Zeitung 

 (loc. cit.) he is reported to say that the conceptacular fruit does not 

 differ essentially from the tetraspores ; that it is, in fact, only a 

 more divided form of the latter; that in FtUota plumosa the 

 transition from one to the other may be followed out ; and that the 

 spores often germinate within the capsule, in which case impregnation 

 is out of the question. In a paper on the Ceramiaceae in the Eeports 

 of the Bavarian Academy, j* ISTageli has some observations on the 

 nature of the fruit of the Eloridere. They occur iu the course of 

 some comments upon a proposed subdivision of the Order by J. 

 Agardh, who separated two groups, viz. the Spyridiese and the "Wran- 

 geliese, on the ground of the different formation of their cystocarps. 

 iN'ageli says : " In most Florideae both cystocarps and tetra- 

 " spores are found; in some, however, the one or the -other kind 

 " of fruit is wanting. Their physiological import is still uncertain, 

 " I have expressed the opinion that the tetraspores are the 

 " female fruit, and that they are impregnated by the antheridia ; 

 " the cystocarps, on the other hand, are the asexual germs. Up 

 " to this time, I find no reason to give up this opinion, and until 

 " it is confirmed or set aside, it is for many reasons the most 

 " probable. Irrespective of the striking resemblance between 

 " the cystocarps, and the gemmae and receptacles of the mosses 

 " and liverworts, two points relative to the CeramiacesB may be 

 " mentioned. In the first place, the tetraspores and the antheridia 

 " are constant in their relative position, and therefore agree in their 

 " morphological signification, whilst the cystocarps vary. The 

 " second circumstance to be noted is the distribution of the three 

 " reproductive organs upon different individuals. Triseciousness is 

 " most usual, so that one plant bears only antheridia, another only 

 " tetraspores, a third only cystocarps. Exceptionally, however. 



* See Ann. des Sc. Nat. 4 Ser. Vol. lii. p. 376. 



f Beitrage zur Morphologie und Systcmatik der Ceramiaceae. Sitzungsberichte 

 der konigl. Bayerischen Acad, der Wiss. 7.w IVEunchen ; Jahrgang 1861. Band ii. 

 p. 297. 



