494 
Max Morse 
thc thick threads and if sbown, would render tke picture confused. 
Care has been taken to determine wketker tbe odd chromosome ever 
becomes temporarily drawn out into tbe form of tbe typical ordinary 
chromosome of tliese stages and tbe writer is certain tbat such is 
never tbe case, tbe pear sbape being evident tbrougbout. 
c) Tbe plasmosomc. Owing to tbe tbick chromosomes, tbe 
plasmosome, which does not stain as densely as tbe cbromosoines is 
distinguishable only witb difficulty in ordinary stains, during tbese 
stages. However, in Auerbach preparations, it may be readily 
located. Cbaracteristically, it maintains, as usual in tbe early stages, 
a position close to tbe odd chromosome. It is sbown thus in figures 
22 and 23. When tbe chromosomes leave tbe poles, tbe plasmosome 
is to be seen lying at tbe edge of the nuclear wall and when this 
breaks down, at the appearance of tbe spindle (fig. 25), it lies in tbe 
mitochondrial mass in tbe outer series of fibres or out in tbe cyto- 
plasm (fig. 28). At no time could one confuse the plasmosome and 
chromosome-nucleolus, or the odd chromosome, during tbese stages. 
Moreover, it may be traced tbrougbout as a homogeneous body, of 
characteristic appearance. It frequently sbows a vacuole within it 
and by this means, especially in safranin preparations, it may readily 
be distinguished. 
5. The metaphase, anaphase and telophase of the first division. 
a) Tbe ordinary chromosomes. The chromosomes come to lie in 
the equator of tbe cell witb tbeir longitudinal axes in tbat plane. 
Some of the bodies precociously arrange themselves for division 
fig. 27) while otbers lag bebind. For this reason, one cell may 
present an almost complete historv of the division of the chromo- 
somes (fig. 30 . The attachment of tbe spindle fibres to tbe chromo- 
somes may be in tbe middle (text-figure III, d and fig. 29), thus pulling 
tbe daughter chromosomes apart symmetrically (text-figure III, e), to 
form a ring (fig. 30); or tbe attachment may be nearer one end of 
tbe cbromosome than tbe other (text-figure III, g and fig. 27) (sub- 
median or sub-terminal attachment), so tbat the daughter chromo- 
somes are pulled out at first into a bracket-like figure (text-figure III, />), 
tbe bodies remaining applied to each other at one end, while tbey 
become completely separated at the other (fig. 30, tbe second chro- 
mosome from tbe right). Those portions of the chromosomes which 
have not pulled apart from one another may be termed "lugs’’; and 
