Lewis.— The Life History of Grijfthsia Bornetiana. 645 
commonly in the third cell from the apex, and rather infrequently in 
cells older than this. 
The divisions of the nuclei of a single cell near the apex are almost, 
though not quite, simultaneous (Fig. 9). In general, the nuclei near the 
apex of the cell are at a slightly more advanced stage of division than those 
near the base. For instance, the nuclei near the apex may show stages of 
anaphase, or even of telophase, while those in the middle region of the cell 
are at metaphase, when the nuclei near the base have reached only the 
condition of prophase (Fig. 9). When there is an accumulation of proto- 
plasm in the apex of the terminal cell preparatory to cell-division, the nuclei 
in this protoplasmic mass may divide considerably before the nuclei of the 
lower part of the cell. In the older cells the nuclei do not show the same 
simultaneity of division. Here small groups of nuclei may undergo mitosis 
while the majority of nuclei are in the resting condition. In the younger 
cells, however, when one nucleus divides, all divide, though not exactly 
synchronously. 
In this connexion, it is interesting to note the behaviour of the nuclei 
in the multinucleate cells of other plants. In the sexual organs of various 
Phycomycetes, the numerous nuclei divide at the same time, as in the 
oogonium of Saprolegnia (Davis, 24), in the oogonia and antheridia of 
Pythium (Miyake, 54), Albugo (Stevens, 76), and Peronospora (Wager, 87). 
Simultaneous nuclear division is reported also in the plasmodia of Fuligo 
(Harper, 38), in Plasmodiophora (Nawaschin, 56), in the ‘ ascus ’ of Hemi - 
asci (Juel, 44, Popta, 62), in the ascus of Ascomycetes (Harper, 37), in the 
basidium of Basidiomycetes (Maire, 53), and in the binucleate cells of 
Uredineae (Sappin-Trouffy, 66). Among algae, approximately simul- 
taneous nuclear division is known in the germinating zygotes of desmids 
(Klebahn, 47), in the young colonies of Volvox (Overton, 60), in Sphaeroplea 
(Klebahn, 48), in Hydrodictyon (Timberlake, 80), in the antheridia of Fucus 
(Guignard, 36). In the vegetative cells of Cladophora , Strasburger found 
that nuclear division is not simultaneous, though he reports that several 
stages of mitosis are to be found in a cell at the same time, which seems to 
indicate that the stimulus to division affects more than one nucleus at 
a time. Among the Archegoniates, simultaneous nuclear division is figured 
by Miss Lyon for Selaginella (52), and seems to be the rule in the develop- 
ing endosperm and in the early divisions in the fertilized egg of Gymno- 
sperms (Coulter and Chamberlain, 20, pp. 20, 31, 41, 83, 98) ; in the free 
cell formation of the endosperm of many Angiosperms (Coulter and 
Chamberlain, 21, pp. 1 65 - 6 , 172 ), and in the developing embryo sac (ibid., 
p. 87). In certain Leguminosae, Guignard (35) reports simultaneous nuclear 
division in the cells of the suspensor. The second mitosis in the gonotokonts 
of Archegoniates is simultaneous in the two nuclei. 
Schmitz, in his studies on the nuclei of Siphonocladiaceae (67, 68) does 
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