34 INTRODUCTION TO CRYPTOGAJVTIC BOTANY. 



appearance to these plants ; but, on the other hand, not to men- 

 tion the total difference of the fruit, their slow growth,* and the 

 extreme difference of texture separate them. There is, indeed, 

 often the same volva-like dehiscence as in Geaster, something 

 similar to which exists in Marattia. This seems, however, 

 merely an exaggeration of what takes place constantly in the 

 formation of adventitious buds and roots, to which it is really 

 more nearly related, than to the more obvious resemblance of 

 Geaster, for in that case the whole of the resemblance is con- 

 fined to the separation and rupture of an investing cellular 

 substance. There is no question about vascular tissue here ; 

 the stems are not formed on an endogenous type, and the 

 mode in which the vascular tissue of the shoot originates, as 

 compared with that of the matrix, is precisely that of adven- 

 titious buds as compared with the especial portion of the vas- 

 cular system to which they belong. In this case, the vascular 

 tissue of the matrix apjDears to exercise the same influence as 

 it would do if the branch was merely a shoot from itself. -|- It is 

 very true that the floral envelopes resemble closely those in 

 some Hepaticoe, a circumstance which occurs also in Podos- 

 temacece ; this certainly is of such a nature as to prevent our 

 saying that Cryptogams are always destitute of such envelopes, 

 but it does not show the slightest affinity. The presence of para- 

 physes undoubtedly affords another point of resemblance, but 

 this is of no great consequence, as analogous bodies exist in 

 many cases of crowded inflorescence. I cannot perceive any 

 essential resemblance between the ovaries and pistillidia of 

 mosses. The pistillidia of mosses, in fact, reasoning from the 

 structure of Club-mosses, if they can be said to be homologous 

 at all, which I do not think to be the case, are not homologues 

 of the ovary, but of the embryonic cavities or corpuscles of 

 Conifers, and therefore must be mere analogues of the ovaries 



* Omhrophytum, however, is said by Poeppig to spring up suddenly 

 after rain, and is eaten like Mushrooms. Hook, fil. in Lindl. Yeg. 

 King., p. 90. 



t Similar observations have been made in Orohanche. The memoir 

 on Balanaphora lately read by Dr. Hooker before the Linujean Society 

 must be consulted on this subject. 



