564 Mr. &ROWN on LyeUia, Leplostomum, and Biubaumia. 



The whole number of capsules examined does not exceed 

 twenty-five ; but as all of these were ripe and of uniform appear- 

 ance and structure, they will probably be considered sufficient for 

 the establishment of the genus. 



To complete the description of LyelUa, male flowers, which, 

 however, probably resemble those of Pohjtrichum and Dawsonia, 

 are still wanting; and although there is no reason to doubt that 

 the calyptra and operculum, both of which I have ventured to 

 describe from fallen specimens, really belong fo this species, yet 

 it would be more satisfactory to find them while still attached to 

 the capsule; for in this state only, the form of the operculum and 

 its probable central connection with the orbicular disk of the pe- 

 ristomium can be absolutely determined. It will be necessary also 

 to examine a greater number of specimens, and perhaps in dif- 

 ferent states, to ascertain absolutely the oeconomy of this moss ia 

 the dispersion of its seeds. It. is evident, however, if the descrip- 

 tion already given be correct, that as far as dispersion takes place,, 

 by the mouth of the capsule, it can only be effected by a contrac- 

 tion or shortening of the columella, and a corresponding retraction 

 within the cavity of the capsule, of the central portion of the 

 peristomium which adheres to it ; and in this state several of the 

 specimens Avere actually found. 



But it is also manifest, both from the great size of the columella^ 

 and its numerous points of connection with the inner membrane, 

 that in this way the whole of the seeds cannot be discharged. It 

 is possible therefore, that in certain circumstances at least, their 

 dispersion may be assisted by the minute pores existing at the base 

 of the capsule. These pores, in the specimens examined, were found 

 to penetrate the outer membrane, or even its external layer only, 

 and being situated below the origin of the seminal bag, their first 

 effect will probably be to accelerate the decay of the internal 



spongy 



