148 PHOTO-MICROGRAPHS. 
It is rather sluggish in its motions, so far as change 
of locality is concerned; but the long and flexible 
neck is kept in constant motion in its active search 
for food, and the cilia upon the surface both of 
body and neck are constantly in rapid vibration. 
An individual of this species being in the field 
of the microscope, it was noticed that there was 
a slight constriction in the centre of the body 
transversely to the long axis of the creature. 
A microscopical friend happening to call at this 
moment, it was determined to follow the whole 
process of division, which was evidently com- 
mencing. The creature might be compared, in 
a rough way, to a glass flask with a long neck; 
and nature was about to make two such flasks 
from a single one —very much as a glass-blower 
would accomplish the same thing — by a constric- 
tion in the middle line of the body, a drawing out 
of the material to form a new neck for the poste- 
rior individual, and finally a complete separation 
of the two at the point of union between the body 
of the anterior and the end of the neck of the 
posterior member of the pair. 
In the case of the living animalcule, however, 
the creature itself took an active part in the opera- 
tion. This was especially the case after the con- 
striction had progressed so far as to leave an 
isthmus between the two portions of about the 
diameter of the neck. Vigorous pulling and tug- 
ging took place between the bodies, until a neck 
of proper length had been constructed for the pos- 
terior member of the firm; and now the con- 
