D. Ward Cutler 
137 
similar to that seen in Plate VII, figs. 37, 38, is produced. The manner in 
which the nuclei lie in regard to one another is quite indiscriminate. As this 
nuclear reconstruction is proceeding the vacuole, with its contained glycogen, 
gradually disappears, but the chromatoid bodies may or may not be present. 
CHROMATOID BODIES. 
These structures were originally supposed to have their origin in the 
chromatin extruded from the nucleus; this was definitely stated to be the 
case by Hartmann in his paper on E. tetragena and also by Elmassian in 
E. minuta. 
Recently, however, there has been great doubt as to the accuracy of this 
statement: thus in a recent publication Dobell and Jepps (1917) make the 
following remark: “these bodies, which we shall call chromatoid bodies (since 
in our opinion they have nothing to do with the chromidium of other rhizopods, 
and are not crystalloid) are, it is true, very generally—though by no means 
invariably—present in E. histolytica cysts.” 
With this view I am in complete agreement. As regards the origin of 
these bodies I am quite ignorant, although a good deal of time was spent in 
trying to discover it. I am convinced, however, that they are not produced 
from the extruded chromatin, for in many cases the chromatoid bodies can 
be seen in the cytoplasm of the cyst before the nucleus has completed its ex¬ 
trusion of chromatin, Plate VII, fig. 27: also it is possible to see, at late stages 
of development, these bodies and the extruded chromatin lying side by side 
in the cyst, Plate VII, figs. 33, 35. Finally the volume of the chromatoid 
bodies is so great as to preclude the idea that the entire mass of their sub¬ 
stance could have been derived from this cast-out chromatin. 
When stained with iron haematoxylin they appear like chromatin, but 
methyl green does not affect them: moreover with Fleming’s tricolour they 
appear as red bodies in contrast to the purple coloured nuclear chromatin. 
With the recognised crystalloid stains the reaction is not characteristic of 
crystalloid substances. 
FURTHER DEVELOPMENT OF THE CYST. 
What occurs when the ripe cyst enters another host has been the subject 
of much speculation by protozoologists. In Entamoeba blattae Mercier (1910) 
has shown that small amoebulae are set free from the cyst, which conjugate, 
and give rise to the vegetative forms. That a similar process takes place in 
other parasitic amoebae has been suggested many times. 
I have not been able to demonstrate with certainty that E. histolytica 
behaves in this way, but many of my results indicate that some such process 
does occur. Further experiments are being carried out, but it seems worth 
while to mention here the probable sequence of events, pending the publica¬ 
tion of my more complete results. 
