388 BOTANICAL GAZETTE [NOVEMBER 
that of Davis for Pellia epiphylla, with the exception that in Pallavi- 
cinia there is no period of rest between the first and second mitoscs. 
I have carefully followed the nucleus of the spore mother-cell 
through all stages, from synapsis to the completion of the resting nuclei 
of the spores, and find that the only structure which could possibly be 
interpreted as a “quadripolar spindle” is that illustrated in fg. 7, 
which is clearly a condition of prophase. It does suggest Farmer’s 
description of a “quadripolar spindle,” and would be so interpreted 
but for the fact that it is followed by bipolar spindles of the normal 
type, through which the chromosomes are distributed by two successive 
mitoses in the usual manner. There is no quadrupling of the primary 
chromosomes or their simultaneous distribution in four groups to form 
the four daughter nuclei, which are the most remarkable features of 
Farmer’s account of the activities of a “quadripolar spindle.” 
The number of chromosomes in Pallavicinia Lyellit differs from 
that reported by Farmer for Padlavicinia decipiens. He states that 
there are four in the gametophyte and eight in the sporophyte. I 
-have not determined the number in the sporophyte, but find eight 
present in each mitosis in the spore mother-cell. This fact is 
clearly shown in the accompanying figures 
I hope soon to present a more detailed account of these events of 
sporogenesis, together with nuclear studies upon other phases in the 
life history of Pallavicinia Lyelliti—ANDREW C. MOORE, South 
Carolina College, Columbia. 
EXPLANATION OF FIGURES I-6. 
Fic. 1. Prophase of the first mitosis; the nucleus has a tetrahedral 
form, the points being directed into the four lobes of the spore mother-cell ; 
fibrillae are gathered at these points but the nuclear membrane has not yet 
broken down; similar stages of prophase were probably considered by: 
Farmer as quadripolar spindles. 
G. 2. The eight chromosomes, grouped in a ring at the nuclear 
plate, are viele from above. 
IG. 3. Metaphase of the first mitosis; the spindle in all respects a 
normal bipolar structure without centrospheres. 
Fig. 4. Anaphase of the first mitosis. 
Fic. 5. Metaphase of the second mitosis; one spindle seen from the 
side; the ae almost perpendicular to the first, shows the eight chromo- 
somes at the nuclear plate 
Fic. 6. Anaphase of the second mitosis; one spindle seen from the 
side; the other seen from one end shows a group of eight grand-daughter - 
chromosomes. 
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