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absorbed in the protoplasm and disappears. So this case needs no 
further consideration. 
The second case regards the parietal Jayer of protoplasm of the 
embryo-sac, which has already become partly divided into cells. Now 
when here also free nuclear divisions take place, the nuclear spindle, 
consisting of connecting threads, behaves at first in exactly the same 
manner as in tissue-cells in which the cell-division follows immediately : 
the system of connecting threads swells laterally and forms a so-called 
nuclear barrel. After this, however, the spindle here is also lost 
in the protoplasm and not until later one sees successive divisions 
take place between these nuclei, progressing regularly from that part 
of the parietal layer of protoplasm that is already divided into cells, so 
that finally a complete pavement of endosperm-cells is formed from 
the protoplasm. This description renders the existence of a connec- 
tion between the nuclear spindle and cell-division not very probable. 
The most important case is the third, in which the just-mentioned 
endosperm-layer divides into two layers of cells by tangentially 
directed walls. Here the nuclear divisions are immediately followed 
by cell-divisions, in the same way as in the formation of various 
sorts of tissues. 
Hence this case, as was proved by comparative observations, must 
be considered as completely analogous with what happens in the 
cells of the growing-point of the roots of Wicia Faba. 
From Mr. Sypkens’ sections it appears that in the two latter cases 
the connecting threads soon cease to deserve that name, as their 
extremities are not attached to the daughter-nuclei but end freely in 
the protoplasm. In Vici faba moreover, the equatorial parts are 
soon dissolved so that the system of connecting threads falls asunder 
into two halves. 
Meanwhile the protoplasm round the nuclei of the parietal layer of 
protoplasm penetrates with its small adventitious vacuoles into the 
space between the daughter-nuclei where the massive complex of 
connecting threads is found. These threads are consequently forced 
asunder towards the circumference and thereby united to spindle- 
shaped bundles, which lie free in the protoplasm; they form what is 
usually called the nuclear barrel. The result is that the two daughter- 
nuclei are at last separated from each other by the same granular 
protoplasm, which also surrounds them and in which also the remains 
of the connecting threads are found. The spindle-shaped complexes, 
formed from these, are united to a barrel-shaped, equatorially swol- 
len, cylindrical mantle, which, if the nuclei are only observed from 
the outside, still seems to join them, although in reality this is no 
