ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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(1) Early passage of the nucleus into the coil state and long per- 
sistence therein, often associated with early longitudinal splitting; e.g. 
Canthocamptus m., Pristiurus f., Larix m., Lilium f. 
(2) Transitory concentration of the coil at one side of the nuclear 
space, Moore’s “ synapsis ” ; e.g. Ascaris m., Canthocamptus f., Lilium 
m. and f., P ter is. 
(3) Relatively early appearance and long duration of a phase cor- 
responding to the “segmented coil” stage. The chromatin elements 
may be loosely distributed, inclining to be peripheral, forming ring and 
cross figures ; e.g. Pristiurus f., Copepoda f., Lilium m. and f. The 
chromatin elements may be densely massed together in the older stages ; 
e.g. Selacliii m., Copepoda f., Larix m., Lilium m. and f., Eqiiisetum , 
P ter is. 
(4) Appearance of a “ main nucleolus ” in the earlier phases, with 
accession of paler adventitious “ accessory nucleoli ” in the later phases ; 
e.g. Selachii m., Copepoda f., Larix m. Individual differences in the 
state of the nucleolar substance ; e.g. Selachii f., Ophryotrocha f., 
Phanerogams m. Persistence of the nucleolar body during division ; 
e.g. Myzostoma f., Lilium m. 
(5) Multipolar spindles as transitional stages to the bipolar form ; 
e. g. Ascaris f., Cyclops f., Lilium m., Larix m., Equisetum. 
(6) Relations to the heterotypic mode of division, — either , a long 
duration of the equatorial plate stage with much thickened and shortened 
chromatin elements (the animal type) ; e.g. Gryllotalpa m., Cyclops strenuus 
f. , Allium m., Pteris ; or , a longer duration of the metakinetic phases 
with double V and cross figures (the vegetable type) ; e.g. Pristiurus m., 
ProstJiecerseus f., Thysanozoon f., Diaulula f., Larix m., Lilium m. 
It does not seem possible as yet to generalise the results ; but Hsecker 
has done service in gathering together the evidence of close parallelism. 
Maturation of Pelagic Teleostean Eggs.* — Dr. T. Wemyss Fulton 
has studied the marked changes which occur in the maturation of the 
ovarian eggs of Teleostei. “ The final stage is characterised by the 
comparatively rapid imbibition of a watery and probably saline fluid 
of low density, which seems to be secreted by the follicle, and is asso- 
ciated with the dissolution of the germinal vesicle and the rearrangement 
of the chromatin. In eggs which become pelagic the volume of fluid 
imbibed is relatively very large, dissolving also the yolk-spherules, and 
reducing the specific gravity of the whole ovum below that of sea water. 
It is in virtue of this change that the eggs of certain marine species 
become buoyant or pelagic (those of fresh-water species could not by this 
device be enabled to float) ; but inasmuch as it also occurs in demersal 
eggs, it is clear that its signification lies deeper. It is probable that 
not only among Teleosteans, but among some other groups, the apparent 
vanishing of the germinal vesicle and the rearrangement of chromatin is 
due to the absorption of fluid from without, and that this is the primary 
and essential meaning of the process.” 
Development of Liver and Pancreas in Birds.j — Dr. M. Brouha 
finds that in the chick the liver develops as usual from a hepatic groove 
* Zool. Anzeig., xxi."(1898) pp. 245-52 (2 figs.), 
f Anat. Anzeig., xiv. (1898) pp. 234-42 (6 figs.). 
