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of granules became transparent here and there, so that the con- 
tractile vesicle, the vacuole, and a body hitherto unnoticed in this 
description, could be easily seen. This body was a globe sur- 
rounded by a dark line, in the midst of an almost complete circlet 
of light. On one side the little globular mass adhered to the sur- 
rounding endosarc ; and elsewhere a clear fluid surrounded it and 
separated it from the granular mass. This is called the nucleus. 
Earlier in the season a number of Amoebae (see series figs. 20-25 
and fig. 13) had been examined which greatly resembled those of 
the active phase of the comparatively quiet form ; and I have 
no doubt, after a study of sketches which were taken of them 
day by day, that they eventually turned into this quiet form. 
The end of the quiet form, which we may consider a phase in 
the life cycle of a thing very different-looking in its youth, 
appears to be two-fold, namely, a bursting or an encysting. 
Very considerable changes go on in the endosarc, such as the 
formation of large vacuoles and the development of more than 
one contractile vesicle, and the endosarc granules become diffused 
in the diaphane, to its edge. Then the whole assumes a globu- 
lar form, and a sudden burst gives vent to the contents (fig- 
26). Or the globular form may become perfectly motionless, 
or rather only the faintest wavy motion may be perceptible at 
the edge (figs. 29, 27), and induration of the thin film of 
diaphane occurs, and a kind of thin shell is formed to the whole 
mass. This encysted stage lasts for a few days in the glass cell, 
but it endures for a long time in the aquarium, and probably 
throughout the winter in many instances. 
Keeping these changes of general shape in mind, let us con- 
sider the first active Amoeba which was seen. This was a most 
exciting Amoeba, and I confess to my astonishment at the paca 
the protoplasmic granular mass poured, I do not know a more 
significant phrase, along. It was, when first seen, in the shape 
of a longish cylinder, flattened at the end which moved in ad- 
vance, and rather pointed at the opposite extremity, which was, 
as it were, dragged along (figs. 2, 7 ). There was no distinction 
between diaphane and endosarc, for the spherical granules, which 
were large and not abundant, were like currants in a dumpling.. 
The diaphane was in excess, and was as usual nearly as trans- 
parent as water, tinted most faintly with neutral tint and very 
minutely granular. One of these transparent Amoebae was one- 
fiftieth of an inch in length, and the streaming and rushing of 
the internal granules, and the coincident flowing out of rounded 
masses of diaphane (lobular pseudopodia), was constant and in 
every direction away from the small end. The grand current 
was central, and in the axis of the Amoeba, and then when 
the granules came with a rush close to the very edge of the 
diaphane they turned outwards and then backwards, and on all 
