BROWN: APOGAMY IN CAMPTOSORUS RHIZOPHYLLUS 29 
erations which developed into prothallia bearing antheridia. Thus 
by adding new solution from time to time when the old became 
exhausted the culture has been kept living up to the present time. 
Some of the prothallia appear normal, having a meristem bearing 
both antheridia and archegonia, while others have given rise to 
proliferations which in turn bear antheridia. 
DESCRIPTION OF THE APOGAMOUS GROWTH 
The prothallium on which the apogamous outgrowth occurred 
was somewhat irregular in shape and only one cell in thickness 
(Fic. 1, P). No sinus was present and at the point where one 
usually occurs in larger and older prothallia a marginal structure, 
or lobe, had formed (Fic. 1, L). 
The apogamous outgrowth began its development as a swell- 
ing in the region of the prothallium where the meristem begins to 
form. This swelling continued to grow, forming a cylindrical pro- 
cess several cells in thickness which became somewhat narrower as 
it developed. After growing for some time in this manner re- 
version to a narrow prothallus-like structure, only one cell in 
thickness with an irregular broadened apex (Fic. 1, AO), took 
place. At one point a branch, irregular in shape and itself show- 
ing a slight tendency to branch, developed (Fic. 1, B;). On the 
opposite side of the prothallus-like oA aka near the ewes an- 
other branch was formed. This branch-p 
elongated, one cell in thickness with a bibad slightly heart-shaped 
apex (Fic. 1, Bz). Rhizoids developed from some of the marginal 
cells near the broadened apex (Fic. 1,R). On one side of the 
elongated part of this branch-prothallium, the marginal and ad- 
jacent cells were smaller and more numerous. From this region 
an archegonium, normal in appearance, developed (Fic. 1, A:). 
The venter of the archegonium was not imbedded in the tissue of 
the prothallus but the whole archegonium extended beyond the 
margin of the prothallus (Fics. 2, 3). 
Two archegonia developed on the apogamous growth near its 
point of origin (Fic. 1, As) and just beyond this point a cluster of 
tracheids was formed in the tissue of the outgrowth (Fic. 1, T). 
As well as could be observed, owing to their imbedded position, 
these tracheids resembled those of a normal sporophyte. 

