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[Vol. 10 , 
ments of chromatic substance remind one of the chromioles of Eisen. 
Vejdovsky shows in his figure 164, a, b, c, d , e, /, and g, Plate IX, the meta¬ 
phase chromomeres in Rhynchelmis and Enchytraeus. It is to be noted 
that this figure presents a striking resemblance to figure 38, g, Plate 3, 
of Wenrich’s (1916) publication. 
Vejdovsky says, further, that the slender halves of the split chromosomes 
consist of chromomeres bound together by delicate, slightly stainable 
bridges. He calls attention to the fact that the same structure was seen 
in the earlier stages of chromosome formation in Enchytraeus and assumes 
that, since they appear again later, their loss during the intermediate 
stages is due simply to the contraction of the chromosomes. 
Later, in 1912, Vejdovsky describes the so-called chromonema which, in 
my opinion, is merely a very accurately described fixation distortion. His 
1907 publication was, it seems to me, a more accurate presentation of the 
facts. One serious objection to the spiral structure was that it permitted no 
simple assumption as to the means for effecting the longitudinal splitting 
of the chromosomes. Vejdovsky avoids this difficulty by explaining, on 
page 21, that the spiral becomes altered, at metaphase, to groups of chroma¬ 
tic bodies in the nature of chromomeres which take up positions opposite 
one another so as to permit an equal longitudinal fission of the chromo¬ 
some. (See his paper of 1912, Plate III, figures 42 and 43). 
As I have already stated, I feel that Miss Merriman (1904) (text fig. 8) is 
not justified in extending her hypothesis of the quadripartite structure of 
the chromosomes to all the subdivisions that may occur, but it is interest¬ 
ing to note the persistence with which the structure shown by my text 
figure 2 is given by investigators. I refer to Bonnevie (1908), figures 7, 
11, 19, and especially 22, Plate XI (text fig. 9), and in particular, to those 
of Nawaschin (1911) (text fig. 10), and Chambers (1915). 
Von Herwerden (1910), working on Chironomus, believes the chromo¬ 
some structure is spiral, but, on account of the granules she observed on 
them, she concludes by associating the latter with the ids of Weismann. 
Schustow (1913) in his figures 4 and 6, Plate XIV (text fig. 11), and 
figures 29-33, Plate XV, shows the anaphase chromosomes to be hollow 
structures. Compare these figures with those of Bonnevie’s (1908) figures 
8, 10, and 22, Plate XI; 56, Plate XIII; and 75 and 79, Plate XIV. Al¬ 
though these figures of Bonnevie and Schustow do not especially show the 
chromomeres, they do illustrate the fact that the stainable material of 
the chromosome is peripherally placed, at least at these stages. The asser¬ 
tion of Schustow that the cross section of the early anaphase chromosome 
is circular whereas that of the late anaphase is polygonal has, I believe, 
no significance with reference to a telophase longitudinal split. 
In discussing the distribution of the chromatin in the chromosome, 
Carnoy (1885) says: 
A l’interieur de ce tube se trouve la nucleine, ou chromatine des auteurs. La maniere 
