— 55 
A second head had one archegonia twice the height of the others. The bases 
of these taller ones were light green, evidently owing to the development of 
the new sporophyte within. On August 9th, the sporophytes showed with a 
hand-lens, and on Sept. 22d they could be plainly seen with the unaided eye, 
being about % inch high. On Nov. 5th, the sporophytes were a little taller, 
averaging about inches high. The stems were reddish brown. The 
calyptra came off easily and the part underneath the calyptra was bright 
green. By Nov. 28th, they had grown to y z inches high, but had not other- 
wise changed in appearance. 
While the observations for the season were not sufficiently full to justifiy 
final conclusions on all points, it was found that the matering of the sperm 
and egg cells is between June 20th and July 14th or better, during the latter 
part of June, for the sporophytes had begun to grow by July 14th, and that 
the sporophytes were discharging spores during the latter half of April. So 
we may conclnde'that in Mnium sylvaticum the time from the maturity of 
the antheridia and archegonia and their contents to the maturity of the 
sporophytes is about ten months. 
Mnium affine ciliare grows in nearly the same places as M. sylvaticum. 
The shedding of the spores from the sporophytes of Mnium affine ciliare 
was recorded for May 16th. On May 23d antheridia were open and dis- 
charging sperm mother cells. The motile sperm cells were very active. 
This is a dioicous moss. On June 5th, four archegonia of one tuft were 
open, and on June 20th in one archegonial head eight archegonia were dark, 
dead, five were open and two were not open but bright. On July 14th, in 
one archegonial head all but two were dark. In another all but one were 
dark. These living ones were about three times as tall as the dead ones. 
They were bright green nearly to the tip. These were the new sporophyte 
plants. On September 22d the new sporophytes could be plainly seen. 
Nov. 5th they were % inches high. The stems were reddish brown to the 
calpytra underneath which they were bright green. During November the 
moss plants put forth a vigorous growth of stem and leaf. 
From the season’s observations Mniuin affine ciliarZ appears to begin to 
mature its sperm and egg cells in the latter part of May, continuing the 
work through most of June, and the sporophyte maturity comes during the 
following May. So for M. affi,ne ciliare the time from the maturity of the 
antheridia and archegonia and their contents to the maturity of the sporo- 
phytes is about eleven months. 
Mnium Drummondii. — Closely associated with M. affine in locality, and 
closely resembling it in appearance was a bisexual moss which I took to be 
M. Drummondii. This moss was shedding spores on May 16th, as was 
M. affine. On May 30th in one head, showing both archegonia and anther- 
idia two archegonia were open. No antheridia were open. On June 1st, 
another head was examined, a few archegonia were open but more were 
closed. All the antheridia were closed. On August 9th, four little sporo 
phytes were seen with the aid of a hand-lens in one head of M. Drummondii. 
I have no later observations on this moss. But these observations indi- 
