746 
Journal of Agricultural Research 
Vol. XXIII, No. 9 
appearance is more exaggerated. From each of these cells two or three 
hyphae now branch out, each composed of one to several cells, the outer¬ 
most being in various stages of disorganization. The nuclei are quite 
distinct; frequently there are two lying close together in each cell. So 
similarly do the cavities in pycnidia and spermogonia originate that one 
can not be certain into which such a structure will eventually develop. 
These protosporophores occasionally produce spores, since a few pycno- 
spores sometimes are found in sections of such young pycnidia, just as 
spores are rarely budded off directly from the thin-walled cells at the 
nrst sporopnores, sometimes scvcicti uuuuius , -. % j *■__ 
first stages of spore formation; c, sporogenous layer now definitely organized; d, young sporophor^ 
each with a single nucleus; e, sporophores from a mature pycmdium, each spore bmudeated, i, sperma 
tiophores from a mature spermogonium. , :i • 
All drawings made with the aid of a camera lucida Zeiss No. 8 ocular, 3-mm. oil-immersion lens. 
very beginning of cavity formation. This may account for the pycno- 
spores sometimes found in spermogonia, to be noted later. 
The ostiolar portion has not been developed in the particular pycmdium 
shown in Plate i, C; central cavity formation began very early, while the 
primordium was still little “carbonized” and therefore in a plastic state. 
Sections often show a large central cavity filled with pieces of the inwardly 
growing hyphae in all stages of disintegration. New buds to form sporo¬ 
phores arise from the subadjacent cells, which as the result of radial and 
tangential divisions become much smaller than those which originally 
occupied this space iu the pycnosclerotium. A still older stage is shown 
