128 BOTANICAL GAZETTE : [aucust 
ventral canal cell or nucleus, it may be regarded that this central 
cell is the functional egg. This agrees with Torreya taxifolia (14). 
In Cephalotaxus Fortunei (15) and C. drupacea (16) a ventral 
nucleus is formed, in the latter disorganizing before fertilization. 
‘This marks the final elimination of the row of canal cells, an elimina- 
tion which has been such a persistent and gradual process from 
bryophytes through pteridophytes and gymnosperms. 
In the earlier stages of the archegonium the central cell nucleus 
is near the upper end of the cell, but as the archegonium matures 
it takes a more central position (fig. 55), the cytoplasm being some- 
what vacuolated and supplied with an abundance of food material, 
some of which stains quite darkly with the staining agents used. 
The archegonial jacket is recognizable from the initial to the. 
mature archegonium, but is not strikingly conspicuous as in some 
other forms, and less so in the mature condition than earlier. 
Usually there is a jacket about each archegonium, with several 
layers of cells between the archegonia, but it is not a rare thing 
to see two archegonia with only a single layer of jacket cells between 
them, and several cases were found in which two archegonia were 
surrounded by a common jacket, this latter condition being an 
‘approach to the archegonium complex found in some of the other 
_ groups of gymnosperms. Several archegonia are usually present 
in a gametophyte, 4-8 being the average number. 
_ SUPERNUMERARY GAMETOPHYTES.—Mention has been ke 
of the fact that more than one megaspore may function. Hor-— 
MEISTER (1) long ago pointed out the presence of more than one 
embryo sac in Taxus baccata, and JAcER (6), STRASBURGER (22), 
and Miss ROBERTSON (18) have found the same situation. STRAS- 
_ BURGER ales oe usually one embryo sac develops; if more 
than 1; on several ‘tales he a 
Vii . ‘7 wee usually 
ee ce Sine : Wt 4 : * 
wel ¥ 
eral nuclei, the two embryo sacs usually lying beside one anoth 
* ee Mg 
S : : and. one case of one above the other. Coxer 2 (9) and Tuouson cs) a ; : : 
