194 BOTANICAL GAZETTE [SEPTEMBER 
seem, like those of the antheridial cavity, constantly more slender in 
form than the bent, club-shaped hairs which occur close to the growing 
point, as was noted by RUGE (’95). 
The early stages of the archegonium were not made out as com- 
pletely as were those of the antheridium, but the stages seen were 
sufficient to show that the archegonia of Monoclea agree essentially 
in the early stages of their development with those of other liverworts 
that have been carefully studied. ‘Thus in jig. 32 we have a young 
archegonium with wall cells, a cover cell, and three axial cells of which 
the lower is evidently destined to form the egg and ventral canal cell, 
while the upper are to break up into neck canal cells. The structure 
is in other words identical in all respects with that of the young arche- 
gonium of all the well-known Marchantiaceae and Jungermanniaceae 
(cj. CAMPBELL ’95, jigs. 2, 17, 46, and GOEBEL ’08, fig. 137): 
The mature archegonium (fig. 33) has a rather broad stalk, a well- 
marked venter, and, as noted by LerrcEes (’77, p. 67) and RucE 
(’93), has also a very long neck (figs. 28, 29, 33). In the cavity of the 
archegonium is found a large, oval egg, a small ventral canal cell, 
and an unusually large number of neck canal cells. The number 
of the latter is larger than ten, and in the case figured was apparently 
fourteen, though the cells shown in dotted outline could not be made 
out clearly, being located just at the level of juncture of the two adjoin 
ing sections from which the drawing was made. 
The number of cells seen in a transverse section of the neck of the 
archegonium is usually six, as shown by CAMPBELL (’98); but occa: 
sionally five and frequently seven or eight were found (figs. 355 34): 
The twisting of the cells of the neck of the archegonium was 
nearly so marked in my material as in that studied by LEITGEB (77) 
and RucE (’93). 
As noted above, the hood-like involucre begins its development 
long before the archegonia are mature, hence, as was pointed out by 
Lerrces (’77), it cannot be the result of fertilization as GoTtscH 
(’58) believed. The archegonium shown in jig. 33 was found in ie 
involucre shown in fig. 28. Since the archegonium is practically pe 
it seems evident that the fertilization of most if not all of the 
gonia must take place before the mouth of the involucre is much 
tracted. The size of many involucres containing embryos points 
