True, Notes on tlie Physiology of tlie Sporopliyte etc. 
43 
because of tlie greater resisting action of tlie solid masses of 
tissued formed. 
Another fact observed may serve to explain tlie great effi- 
ciency of this protecting structure. Although torn away from its 
place of growth at an early stage in tbe life of tlie sporopliyte, 
tlie cells of tlie calyptra are fonnd to be living until sliortly be¬ 
töre it is rnptured by tlie increased size of tlie enclosed capsule. 
Having no organic connection during this long period with any 
source of food supply, it must maintain itself independently. 
Since each cell contains a good nuraber of cliloroplasts, this me- 
thod of support is easily surmised. The source of the neccessary 
steady water supply is doubtful. O 11 renioving the calyptra from 
the sporopliyte, minute drops of water were usually seen adhe- 
ring to tlie sporopliyte, and the examination under low magni- 
ticatiön of tlie sporopliyte bearing the calyptra in position re- 
vealed the presence of water more or less hlling the upper part 
of the calyptra. Whether this water is excreted by the sporo- 
phyte and maintained in place by tlie calyptra, or whether tlie 
calyptra itself has tlie ability to condense or absorb water through 
its much folded outer snrface, can hardly be said. At all events, 
the calyptra is doubtless supplied with the substances and con- 
ditions necessary for carbohydrate formation, and for its nearly 
independent, temporary nutrition. Thus in tlie developing spo- 
ropliyte, three organicalli unconnected structures are present, 
each to a considerable extent capable of independent nutrition. 
In Mnium , growing on the damp leaf-mould in the woods, 
the danger of desiccation is minimal and the calyptra seenis to 
refiect this in its structure. It is pointed at the distal end and 
widens somewliat rapidly toward the base. There is 110 close 
clasping of the seta at the base, and tlie calyptra fall off at a 
much earlier stage than in Funaria. It seenis to me that a 
thorough study of the structure of the calyptra and its ecological 
relations to the sporopliyte offers an interesting problem in ways 
and means in Archegoniates. 
Another question of some inte riest was raised in connection 
with this study. It was noted that in tlie young stages of the 
Funaria sporopliyte, the distal end, containing the regions of 
cell division and most of the zone of elongation, was thrust into 
the calyptra to the very extreme of the long, beak-like portion 
and was not withdrawn to the capacious sac-like part un¬ 
til the enlargement ol“ the capsular rudiment was about to begin 
or was already to be traced. This withdrawal of the end of the 
sporopliyte to the- more roomy portion of the calyptra could be 
seen in progress before any noticeable enlargement of the latter 
had taken place. TTsually, liowever, the curvature of the seta 
began contemporaneously with the beginning of the withdrawal. 
In wliat way this withdrawal was ef'fected was not easily ex- 
plained. It seems probable that the inner surface of the beak- 
like portion of the calyptra is moist and offers little friction to 
the smooth surface of tlie slender sporopliyte. (5) As the cur- 
