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Arlow Burdette Stout 
substance along tlic line of the spirem. At this stage it is seen that the 
spirem remains attaclied by fibrils to the nuclear membrane at certain 
points as at a, and h, df figure 20 as if it were viscous and adhered to it. 
The chromosomcs may appear even to be attached together in various 
directions by fibrils as shown in figure 20. The serial arrangement is, 
however, readily traced at many points at least for short distances. The 
Connections between the chromosomes in the line of the spirem become 
more and more conspicuous. The chromosomes e\ddently become elon- 
gated until they form a thin continuous chromatic thread, the leptoneme 
of WI^WARTER (1901). This sph'em is much tangled, folded on itself or 
crumpled. The attachments to the nuclear membrane noted above 
persist for some time producing such appearances as are shown in figure 21. 
This figirre resembles superficially that produced by second synapsis as 
described by Miss Sargaxt (1896 and 1897), Allen (1905), and others, 
except for the thinness of the spirem. There is some indication of a 
parallel arrangement of the threads in this stage. This stage is the first 
figured by Juel (1900), but there can be no doubt that it is a presynaptic 
stage. The attachments of the chromatic thread to the nuclear mem- 
brane are not permanent. They break away and when the synaptic 
knot is fully formed the entire chromatin thread is drawn together into 
a rather compact mass. It may be possible that delicate Unin fibres 
still connect the mass with the nuclear membrane, but I have not been 
able to bring them out by staining. 
The diameter of the nuclei in the presynaptic stages varies from 
8,5 H to ocasionally 10,0 a. Tliere has been a growth süghtly in excess 
of that exhibited by the nuclei in the prophases of pre\’ious divisions. 
The synaptic knot usually lies to one side of the nuclear ca^dty and 
it may or may not envelop the nucleoles. There is, however, no such 
Orientation of the knot vith reference to gravity as has been especially 
described by Cardiff (1906). 
There can be no question that synapsis as here described and figured 
is a normal contraction stage and is not as Lawson (1911a) Claims simply 
due to a swelling of the nuclear membrane away from the chromatic 
reticnlum. L.\wson considers that there is no decrease in the chromatin 
area during synapsis in Smüacina. This is certainly not the case in 
Carex aquatilis. Figure 22 shows an entire nucleus with a typical sy- 
naptic knot at its greatest contraction. The chromatin mass measures 
3,75 u in diameter, while the chromatin shown in figure 20 extends 
through a diameter of 7,0«. 
The evcnts of synapsis are in .sharp contrast to those of the pro- 
