16 
SPERMATOGENESIS OP NORMAL 
exists as Moore^ figures in the testicular cells of the elasmo- 
branchs, or Lenhossek^ in those of the rat. 
In the growing cell the cytoplasm has the appearance of a 
granular mass throughout which fine ramifying fibres can be 
detected occasionally. The sphere at times exhibits a delicate 
fibrous structure but this was not observed frequently and may 
have been due simply to the action of the reagents. 
Synapsis. 
As soon as the growth of the primary spermatocyte is com¬ 
pleted, the nucleus, which is voluminous and apparently turgid 
with sap, undergoes a curious change. There is a marked 
drifting of the nuclear contents to that side in contact with the 
sphere (Fig. 7). This phenomenon is the same that Moore^ 
recognized in the maturation of Elasmobranch sperm cells and 
which together with the accompanying fusion of pairs of chro¬ 
mosomes he has designated by the term synapsis. A similar 
union of the chromosomes occurs in the, pigeon, for at the en¬ 
suing division only eight chromosomes appear. Thus, a 
pseudo-reduction in Riickert’s^ sense occurs. 
In the collapsed and tangled mass of the nuclear elements 
that have passed to one side of the nucleus, no distinct arrange¬ 
ment can be recognized. The remainder of the nucleus seems 
to be absolutely devoid of any contents which will react to 
stains. Often one or more stiff bristle-like fibres or strands of 
what appears to be the linin material project out from the mass 
across the vacant area of the nucleus. The ends of shorter 
fibres are seen sometimes bristling out from all sides of the 
heap. 
If saffranin and gentian violet are used for staining, one 
observes granules and clumps of chromatin taking a deep red 
stain, mixed indistinguishably with a bluish or violet mass of 
linin. No distinct chromosomes as observed by Montgomery"^ 
1. Moore, J. E. S. On the Structural Changes in the Reproductive Cells 
During the Spermatogensis of Elasmobranchs Quart. Journ., XXXVIII, 1893. 
2. Loc. cit., p. 5. 
3. Ruckert, J: Zur Eireifung bei Copepoden: An. Hefte, 1894. 
4. Loc. cit., p. 12. 
