564 Mr. Brown on Lyellia, Leptostomum, and Burbaumia. 
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. l 
To complete the description of Lyellia, male flowers, which, 
however, probably resemble those of Polytrichum 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 to 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 ceconomy of this moss in 
the dispersion of its seeds. It is evident, however, if the descri p- 
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 were 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 
