ARCHEGONIUM AND SPOROPHYTE OF TREUBIA INSTGNIS 267 
separates the lower or ventral region from the neck; and in the three 
primary peripheral cells of the neck, a longitudinal division inaugurates 
six rows of neck-cells. In the older archegonium of Treubia, how- 
ever, other longitudinal walls may appear, so that a cross-section of 
the neck, especially in its lower part, shows sometimes as many as 
nine peripheral cells, while most of the Jungermanniales have but 
five. As a result of this increased number there is not a clearly marked 
line between the venter and the base of the neck (fig. 3, C, D). 
Figure 2, C, D show longitudinal sections of two young arche- 
gonia in which the central cell of the venter is still undivided, and the 
primary neck canal-cell has divided twice. As in other liverworts, 
there is later cut off from the central cell, the ventral canal-cell (fig. 
3, C, v), and there is a further division of the neck canal-cells. None 
of the specimens examined showed more than eight neck canal-cells, 
but Griin gives a figure showing sixteen, which he says is the normal 
number for the fully developed archegonium. 
The cells forming the wall of the venter undergq periclinal divi- 
sions, so that at maturity the egg is surrounded by a double layer of 
cells. 
The number of archegonia in a group, in the specimens examined 
by the writer, was about a dozen. Mingled with the archegonia are 
numerous paraphyses (" Paraphylls"), which may be either simple 
cell-rows, or more or less expanded and branched scales. The marginal 
cells of these scales are often secretory organs, exuding a mucilaginous 
matter like that developed from the mucilage papillae on the lower 
side of the leaves. 
The Embryo 
Griin has described somewhat at length the structure of the older 
sporophyte, but he was unable to get the earliest stages. The 
account here given is far from complete, owing to the limited amount 
of material that was available; but it is hoped that it will be sufficient 
to make clear the most important points in the early history of the 
sporophyte. 
The earliest divisions were not seen, but it is pretty certain that 
they are transverse as in all other Jungermanniales that have been 
investigated. It is also reasonably certain that the lowermost seg- 
ment (or segments?) are devoted to the formation of the conspicuous 
haustorium which is a marked feature of the young embryo. All of 
