■8 Wisconsin Academy of Sciences, Arts, and Letters. 
Heim (50) in 1896 describes apogamy in Doodya caudata. 
The prothallia bear archegones and antheridial sacs, and sexual 
reproduction may take place. When a normal embryo does not 
form, the tissue about the sex organs grows out into “arche- 
gonial projections” or “antheridial projections” as the case 
may be. On these tissue masses, of which there may be thirty 
on one prothallium, the sporophyte buds form much as in Pteris 
'Cretica. Only a few of those upon one prothallium can sur¬ 
vive. 
Lang (64) in 1898 made some interesting experiments upon 
the following ferns: 
Scolopendrium vulgare, N ephrodium dilatatum, Nephrodium 
Or&opteris, Aspidium aculeatum, Aspidium angulare, (two 
varieties) Athyrium niponicum, Aspidium frondosum, Poly po¬ 
dium vulgare, and Athyrium filix-foemina. Eight of the nine 
ferns studied, were not known to reproduce in any but the 
usual way. The prothallia were maintained under conditions 
which favored vegetative growth but prevented fertilization. 
In all of the cultures the prothallia sooner or later made at¬ 
tempts, often abortive, at producing sporophytes apogamously. 
In Scolopendrium vulgare, for example, Lang finds that when 
fertilization fails to take place, the meristem at the apical notch 
or the tissue just back of it on the ventral side of the prothal¬ 
lium develops into a massive cylindrical solid outgrowth, 
radial in structure and often two centimeters long. The in¬ 
terior of this mass may contain only parenchyma or there may 
'be isolated tracheids or even a fairly well organized stele. In 
some cases there are rhizoids on its lower surface, in others, 
roots arise endogenously, break through and grow down into 
the ground. The apex of this cylindrical vegetative out¬ 
growth may grow out into a flattened pro thallium returning to 
the typical gametophyte phase, or on the other hand it may 
give rise to a sporophytic bud with leaf, stem and root. This 
cylindrical process bears achegones and antheridial sacs on 
all sides. If fertilization is allowed to take place a normal 
embryo can form. If not, the tissue about an archegone forms 
an “archegonial projection” upon which may be formed a 
group of sporanges. These sporanges are often ill-formed but 
