458 
J. GEAY. 
preparations this cannot be insisted upon. Whether it is 
legitimate to compare these figures with figs. 23 and 25 of G. 
Hertwig (5) is doubtful. In no case were “vesicles’^ found 
within the nuclear membrane of these eggs (cf. fig. 30). 
Series E. : E. esculent us. — Eggs treated with 50 c.c. 
sea-water -4- 9.V c.c. M. NaCl solution. 
Fig. 31 shows an extreme effect of hypertonic solutions on 
an egg. Similar figures were obtained for first segmentation 
divisions. This is exactly comparable to Konopacki’s (7) 
results on the eggs of Echinus microtubercutus treated 
with a slightly weaker solution (cf. his fig. 18). 
Whether we are justified in assuming that the first mitotic 
figure of the particular egg which is figured was similar to 
those of the second division is doubtful, for it is possible that 
the pathological effect of the hypertonic solution did not 
affect the chromatin until the first division was over. 
Konopacki assumes that the dark streaks are entirely chro- 
matic in nature, but my preparations tend to show that part of 
the darkly stained material is derived from the spindle fibres. 
Series F.: E. esculentus. — Eggs treated with 50 c.c. 
sea-water -f 20 c.c. 2i M. NaCl solution for fifteen minutes. 
This batch showed very few mitotic figures, most of the 
eggs having evidently failed to develop. The figures avail- 
u,ble showed that, as a whole, division is normal although 
there is a tendency for the omission of one or more chromo- 
somes (fig. 32). 
Series G.: E. esculentus. — Eggs treated with 50 c.c. 
sea-water -f 20 c.c. M. NaCl solution for 30 minutes. 
In these eggs the hypertonic solution has visibly affected 
both the chromatin and the cytoplasm. Very few eggs 
develop, and those which do so show some sign of cytolytic 
action. Figs. 33 and 33 a show a 2-celled stuge in which 
the first division of the egg was normal, but which was then 
preparing to divide very irregularly. There is a tendency for 
omission of chromosomes from the spindles in this egg. The 
centrosomes are contracted to small and compact bodies 
which stain darkly with Heidenhaiu’s htematoxyliu. 
