Nichols, A morphological study of Juniperus communis var. depressa. 231 
cannot be considered as completed until the “half chromosomes 
derived from the male and female nnclei respectively fnse together 
at the poles of the first Segmentation spindle”. In the European 
J. communis Noren (1907, p. 43) describes a rather pecnliar con¬ 
dition. He writes: “Die kettenförmig mit einander verbundenen 
Pseudonucleolen verschmelzen schließlich mit einander (1. c., Hg. 78), 
wodurch dicke, unregelmäßige Fäden entstehen. Auf diesem Stadium 
können noch die den resp. Kernen zugehörigen Chromatingruppen 
deutlich unterschieden werden, also auch noch nachdem die Mem¬ 
branen zwischen den Kernen völlig verschwunden sind”. 
The behavior of the chromatin in J. communis depressa is 
very similar to that observed by the above mentioned writers, but 
no indications were found that the spirems originate, in the manner 
described by Noren, from the “melting together” of the pseudo- 
nucleoli. For one or two days after the union of the male and 
female nuclei the fusion nucleus to all appearances continues in a 
resting condition. Then there begin to appear in the nucleus 
numerous moreorless connected, moniliform threads which exhibit 
a beautiful differentiation into chromatin and linin (fig. 103). These 
Strands run all through the nuclear cavity, and, while it is im- 
possible to make out with certainty whether two spirems are 
present at this time, such is presumably the case. The threads 
soon draw away from the nuclear membrane, become more closely 
coiled, and in the stage represented by fig. 104 it can be clearly 
seen that two distinct spirems have been organized. At the same 
time the whole band comes to stain uniformly, and the nucleolus- 
like structures disappear. The infrequency with which the con¬ 
dition described here has been observed is easily accounted for 
by the difficulty with w 7 hich suitable preparations are obtained. 
Fig. 104 represents the only instance, out of over 2000 archegonia 
examined in which this stage might be looked for, where it 
is possible to distinguish the male and female elements in the 
fertilized egg. 
Segmentation into chromosomes takes place rapidly and ap- 
parently in the usual manner, the chromosomes become oriented at 
a common equatorial plane (fig. 105), and a broad, multipolar 
diarch spindle is organized. At this period coarse, granulär threads 
are sometimes seen in the protoplasm of the nucleus outside the 
spindle, but their relation, if any, to the formation of the spindle 
in obscure (cf. Ferguson 1904, figs. 228—230). The multipolar 
diarch quickly becomes bipolar, and the manner in which the 
chromosomes split and separate toward their respective poles is to 
all appearances identical with the process as described in the di- 
vision of the central cell nucleus. Fig. 106 represents the telo- 
phase of this division. The chromosomes have drawn together at 
the poles, and nuclear membranes are about to be formed. By 
this time the membrane of the fusion nucleus itself has disappeared, 
although the nuclear cavity still remains clearly delineated, while 
the connecting fibers are still visible between the massed chro¬ 
mosomes. After the development of membranes about the two 
