43 8 Moore. — Essential Similarity of Chromosome 
Weismann’s conception of the universality of the c Reductions- 
theilung ’ has broken down, and apart from the universality 
once claimed for it, the ‘ Reductionstheilung’ is, as Dr. Haecker 
says himself, not of much theoretical importance. 
With respect to the similarity between the synapsis among 
animals and plants, it was shown some time ago by Farmer 1 
and Belajeff 2 , that the chromosomes formed during the division 
of the spore mother-cells of lilies had not the structural 
character which had hitherto been assigned to them, and the 
suggestion was thrown out by Professor Farmer that this 
mitosis probably partook of the nature of a heterotype. 
The extremely interesting conclusions which must follow 
from the establishment of something more than a mere re- 
semblance between the synaptic changes in the reproductive 
cycles of animals and plants, induced Professor Farmer and 
myself to institute a joint comparison between the great sper- 
matic heterotype in Tritons and the division of the pollen 
mother-cells of lilies 3 . 
Our results are briefly these : (i) That the division of the 
pollen mother-cells in lilies is a heterotype. (2) That during 
the synaptic rest which precedes it. in both animals and plants, 
the chromatin of the nuclei is always more or less contracted, 
either to the centre or to one side, just as in the corre- 
sponding stage in the spermatogenesis of A scar is described by 
Brauer. This condition of the nucleus in plants has already 
been figured and described by Strasburger, but it has been 
generally believed by botanists to be an artificial product, 
caused by the preservative reagents used. 
Our observations, however, seem to show that it is in reality 
nothing of the kind, and that the better the general preserva- 
tion of the cells, the more marked is the appearance of nuclear 
1 Ueber Kerntheilung in Zz 7 zzm-Antheren, besonders in Bezug auf die Centro- 
somenfrage. Flora, Heft I, 1895. 
2 Zur Kenntniss der Karyokinese bei den Pflanzen. Flora, Erganzungsband, 1894. 
3 Farmer and Moore, On variations in the genesis and structure of the 
chromosomes in plants and animals. Anat. Anzeiger in the hands of the 
publisher. 
