480 Harper. — Cell- Division in Sporangia and Asci. 
taneously into a single palisade layer of rod-like spores. 
This spore layer is bounded inside and out by a plasma- 
membrane (Hautschicht). Later the spores migrate from 
their first position and collect in a ball at the apex of the 
sporangium. No intersporal protoplasm is to be observed, 
but an outer and inner boundary layer of protoplasm about 
the spore-mass is present. In P. macrosporus , instead of a 
single layer three layers of spores are formed at once from 
the wall-layer of protoplasm in the sporangium. The spores 
here also migrate to form a ball at the apex of the sporangium. 
This spherical mass of spores is surrounded by a space con- 
taining cell-sap and numerous radially arranged protoplasmic 
threads and plates. These spores contain from four to seven 
nuclei. The protoplasm outside the spore-mass is also 
multinucleated. In this last point can perhaps be noted 
something similar to the multinucleated periplasm in the 
oogonia of Cystopus. Popta describes the cleavage in these 
cases as simultaneous rather than progressive, which would 
suggest division by cell-plates rather than by superficial 
furrows. 
My own observations concern the phenomena of cleavage 
and spore-formation in certain sporangia of the lower Fungi, 
which perhaps may be taken as typical at least of the groups 
to which they belong, and further an account for purposes 
of comparison of the process of free cell-formation in the asci 
of Lachnea scutellata. 
I shall describe the process in species from three genera 
of the lower Fungi, Synchitrinm , Pilobolus , and Sporodinia. 
The sporangium of Synchitrinm may represent a type of 
the cyst-like reproductive bodies of the one-celled fungal 
organisms, while Pilobolus and Sporodinia are types of the 
vegetative reproductive bodies of the Phycomycetes. Whether 
these sporangia are homologous with the zoosporangia of 
the Algae is perhaps still an open question, as we shall see 
later. In all three cases spore-formation consists in the 
cleavage of a multinucleated mass of protoplasm and the 
formation of numerous smaller reproductive bodies. 
