48 Farmer . — Studies in Hepaticae : 
becomes diffused out into them. The objects are too small to 
admit of this suggestion being verified by observation, but 
I have already shown T , and my results have been confirmed 
and extended by Zimmermann 1 2 , that the nucleolus may break 
up and pass out into the cytoplasm during division in pollen- 
mother-cells, so there is no inherent improbability in the view 
that a similar state of things obtains here. The chromatic 
elements of the nucleus next begin to become individualized, 
and, so far as I have been able to determine, on studying many 
hundreds of preparations, they do so in an irregular manner. 
It is possible that the spirem-stage may occur, as it certainly 
does in the vegetative cells of the sporophyte, but I have never 
seen it. Four chromatic droplets form the first positive 
evidence of approaching division which I have seen in the 
nucleus. The quadripolar spindle however has been formed 
before these four chromosomes appear. In several instances 
I have seen the centre of the nucleus occupied by a large mass 
of chromatic substance, which was distinctly four-lobed, as 
though the four bodies, already referred to, arose by the 
breaking up of an original lump in this way. Fig. 30 is 
a camera-lucida-drawing of such a case, and I may say that 
I possess photographs of this actual specimen which exhibit 
exactly the same appearance as that shown in the drawing. 
Shortly after the appearance of the four chromosomes, their 
arrangement becomes more regular, and their number is 
increased by division to eight. Their shape is not that of loops , 
as is the case with the vegetative nuclei, but that of rods, and 
it may be remarked that this difference of form is extremely 
common between the vegetative and reproductive nuclei of 
the same plant, e. g. in Lilium Martagon. The eight chromo- 
somes now point off in pairs as though about to travel to the 
lobes of the spore-mother-cell, and I believed until recently 
that only two chromosomes went to each lobe. I have how- 
ever since found two instances, so clear as to admit of no 
1 J. B. Farmer, On nuclear division in the Pollen-mother-cells of Lilium Mar- 
tagon , Annals of Botany, vol. VII. 
2 Zimmermann, Beitr. z. Morph, u. Physiol, d. Pflanzenzelle, Bd. II. Heft 1. 
