Katharine Foot and E. C. Strobell 297 
dense chromosome of Photos. 19, 20, and 21 should be confounded with 
the eccentric, for in all of these preparations its position within the 
group close to the microchromosome makes its identification as a lagging 
eccentric chromosome highly improbable, and more than this, in the 
earlier stages, where we find one or two dense dyads there can be no 
question of confounding them with the eccentric chromosome (see pp. 
289-90 for a detailed description of these dyads). 
Photos. 23, 24, and 25 show three anaphases of the second spindle. In 
these preparations the chromosomes are closely grouped, preventing the 
identification of each individual chromosome, but in all these prepara- 
tions, the evidence points to a division of al/ the chromosomes. 
Photo. 26 shows a later anaphase of the second spindle. The eccen- 
tric chromosome can be identified on the left periphery of the groups by 
its typical position outside the two circles of chromosomes. It has not 
yet divided, but its dyad form and distinct transverse furrow, we believe, 
can have no other meaning than forecasting a division. This evidence 
is repeated in Photo. 27. In this preparation the eccentric has the 
same typical position shown in Photo. 26, and its dyad form is plainly 
demonstrated. 
Photo. 28 shows the eccentric chromosome after its division has oc- 
curred. Its typical position, outside the two circles of chromosomes 
assures its identification, and we must interpret it as the eccentric chro- 
mosome, the division of which is so clearly foreshadowed in Photos. 26 
and 27. Only nine of the ten large chromosomes are clearly differen- 
tiated at each pole of this spindle, but it is quite superfluous to even 
comment upon the possibilities of individual chromosomes being obscured 
in such small spindles and especially in view of the fact of the tendency 
of the chromosomes of the second telophase to contract at once into 
almost a solid mass of chromatin (see Photos. 30, 31, and 46). It is 
only when the eccentric is retarded in division, that the contraction of the 
chromosomes at the poles is often delayed and the individual chromo- 
somes are differentiated. It is instructive to compare the three Photos. 
(26, 27, and 28) with telophases of the first spindle, for example, Photos. 
2, 3, 10, and 14 to 18. 
In Photos. 29, 30, and 31 we have another series of photographs show- 
ing the division of the eccentric chromosome of the second spindle. In 
Photo. 29 every chromosome is shown, and the dyad form of the lag- 
ging (eccentric) chromosome is so pronounced that it is almost a demon- 
stration of its division. In Photo. 30 the division of the lagging chromo- 
