224 BOTANICAL GAZETTE [ocTosER 
divided. I have even found some evidence that sausage-shaped 
Masses are cut out of the center of larger masses by means of a 
cylindrical cleavage furrow. It is very common to find semi- 
cylindrical masses cut from the surface of the protoplasm by 
two furrows which curve toward each other so as to form a 
trough-shaped cleavage surface. All of the above varieties as 
to form and direction of the cleavage furrows are illustrated in 
jigs. 1-4. 
At and immediately prior to the time when cleavage com- 
mences in Fuligo, its nuclei are all in the resting condition. 
None of the nuclei indicated in jig. t were dividing. A very 
little later, almost simultaneously with the formation of the first 
superficial cleavage segments, the nuclei throughout the entire 
aethalium begin to divide karyokinetically. In some cases it 
may be that the peripheral. nuclei commence to divide earlier 
than those which lie deeper. But the difference, if it exists, 
generally is a very slight one. On the other hand, the process 
of division seems to begin progressively rather than simultane 
ously in different parts of the aethalium, regardless of depth 
from the surface. This is shown by the fact that in examining 
sections different stages of karyokinesis are found in different 
parts of the same section. For example, all the nuclei in a cer 
tain region a few hundredths of a millimeter in diameter may be 
in the equatorial plate stage. Moving from this region in one 
direction one will find a gradual transition to the anaphase 
stages. Moving in another direction one may find prophases, 
or one may find nuclei in anaphase on all sides of a region oe 
ing only equatorial plates. There is no constancy in the order 
of stages which will be found in moving from the peripheral ” 
the central or deeper portions of a section cut radially to the ” 
face of the oval, cake-shaped aethalium. It is an absolute peo . 
however, that widely separated stages in division Bae 
found in close proximity to each other, at least in a“ , 
masses of protoplasm; and generally, passing over one : alium 
humerous lacunae, which, as noted above, pierce the aeth ‘- a 
in all directions, does not involve any sudden transition 1? 4 
