448 
Campbell . — The Gametophyte and Embryo of 
bear to the organs of the young sporophyte. It is possible that r in 
section III may be the beginning of the primary root, but this is by no means 
certain. 
Text-fig. 4, B, shows two somewhat oblique longitudinal sections of an 
embryo with about ten cells. This embryo was decidedly elongated 
vertically instead of having the globular form of the embryo shown in A. 
It was somewhat pointed above, a condition which is sometimes found also 
in B. virginianum. Indeed, it may be said that in general the earliest 
stages of the embryo in B. simplex resemble more nearly the corresponding 
stages in B. virginiamim 1 than those of B. lunaria . 
Text-fig. 5. A. Three longitudinal sections of an embryo in which the basal wall is no longer 
certainly visible. The cell r, in III, may be the root-initial, x 300. B. Young embryo showing 
the basal wall, b , clearly, c. Three transverse sections of a young embryo ; I, section next the arche- 
gonium. x 300. 
A young embryo of seven ceils (Text-fig. 4, B) had two cells in the 
epibasal portion and five in the hypobasal, the latter quite irregularly 
disposed. The resemblance to B. virginianum is also shown by a com- 
parison of the transverse sections. Text-fig. 5, C, shows such a series, and 
it is much like a similar series of B. virginianum , shown in Fig. 31 of the 
writer’s monograph of the Eusporangiatae. In both cases the section next 
the archegonium was composed of two equal cells, showing an absence of 
octant walls in the epibasal region. 
In a somewhat older stage (Text-fig. 5, a) there is a large cell, r, in 
the hypobasal region which in form and position suggests that it may be 
the initial of the primary root ; but as no stages were found between this 
and the very much older embryo shown in Text-fig. 6, in which the apical 
cell of the root was plainly visible, this is by no means certain. 
1 See Campbell, The Eusporangiatae, Figs. 28-31. 
