446 
George Arnold 
c) These segmeuts are in number equal to half the number of 
somatic chromosomes. Certainly there are never, even in the lepto- 
tene nuclei, as many segments as there are somatic chromosomes. 
Nor do the segments pair up longitudinally, as deseribed bv Schleip. 
d) There is a well marked resting stage preceding the 2nd. 
meiotic di vision, characterised by the formation of a vesicle, of the 
nature of archoplasmic vesicle of the spermatid, which however, 
breaks down in the metaphase. Possibly this vesicle is derived from 
the archoplasm, but its origin has not been observed. 
e The spermatid bores its way out of the cytoplasm by means 
of the archosome. 
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