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R. A. HARPER 
(2) is inclined to discard the erroneous description by Dangeard which 
makes the cleavage in Synchytrium taraxaci simultaneous while 
Barrett holds Dangeard's account is true also for Olpidiopsis. 
Wager (34) notes again that the lines of demarcation of the spore- 
origins, in the cysts of Polyphagus, appear, disappear and reappear 
again as the older authors have observed in the sporanges of the 
Saprolegniaceae. He describes spore formation as due to cleavage 
from the center outward. When the clefts reach the plasma membrane 
the sporange contracts and perhaps the spores also swell. 
Moreau (23) describes the spore formation in Circinella conica as 
beginning with an extreme vacuolization of the protoplasm. The 
vacuoles become irregular in form and break the spore-plasm up into 
fragments. The fragments are irregular amoeboid bodies and remain 
for some time connected by strands which finally break through. 
Just how this process is related to the cleavage by vacuoles as seen in 
Pilobolus and Phycomyces is not clear and Moreau's figures give 
little idea as to just how the vacuolization results in the fragmentation 
of the protoplasm. Moreau finds the cleavage in Rhizopus and 
Phycomyces to be essentially as described by Swingle and holds that, 
as in Circinella, contraction phenomena are an essential phase of the 
process. In Mucor spinescens Moreau finds that vacuolization of the 
spore-plasm results in the formation of long strands, with the nuclei 
in a single series. These strands become nodular or catenoid and 
break up into uninucleated or sometimes several nucleated spores. 
For the Conjugatae and Desmids there is general agreement that 
as in Cladophora the cell divides by a circular cleavage furrow with 
simultaneous wall formation. Lutman (21) has described the process 
in detail for Closterium. 
The conditions in algae such as Dictyota and Sphacelaria need 
further study. Swingle (30) and Mottier (24) describe a peculiar 
sort of plate formation without the presence of a central spindle. 
Tuttle (32) describes nuclear division in Oedogonium but says nothing 
definite as to the method of cell division. 
McAllister (22) has recently described a cell plate formation in 
Tetraspora which is quite like that of the higher plants. The inter- 
es^ng possibility is thus suggested that as McAllister argues those 
algae which are in the line of ascent to the higher plants may have 
quite a different method of cell division than that found in Cladophora, 
Hydrodictyon and other well known types. Whether or not this con- 
