172 J. IT. CUNNINGHAM. 
them is seen to be made by an intermediate mass of clear 
protoplasm, as in fig. 2, d. Besides the elements already 
mentioned there are seen in each preparation several others. 
There are spindle-shaped bodies produced into an attenuated 
process at each end (fig. 2, a) ; in these a nucleus is not usually 
visible. There are also a large number of less regularly shaped 
masses of clear protoplasm running out into similar attenuated 
processes, some being bipolar, some multipolar. In the 
majority, though not in all of these are seen one or two, or a 
number of bodies in all respects similar to the heads of sperma- 
tozoa. In some cases these bodies, which may conveniently be 
called sperm-nuclei, are seen to be connected, as in fig. 3, a, 
fig. 1, a, with a mass of protoplasm by a thin protoplasmic 
filament similar to the tail of a spermatozoon. In other cases 
the sperm-nuclei are situated in the substance of processes of 
the protoplasmic masses, and in other cases again there are 
several of them scattered through the main body of these 
masses. The various conditions seen irresistibly suggest the 
idea that the sperm-nuclei are capable of motion, that they are 
pushing themselves out of the protoplasmic masses, drawing a 
shread of the viscous protoplasm behind them, and that when 
the connection between the mass and the thread breaks, the 
nucleus with the portion of the thread attached to it forms an 
independent spermatozoon. I believe that all this really takes 
place, but that it is the clear protoplasm which effects the 
changes, the sperm-nuclei remaining passive. For several 
times I have seen the protoplasm actually in motion like the 
tail of a spermatozoon. For instance, the filament connecting 
6 and ¢ in fig. 2 was slowly vibrating from side to side and 
gradually lengthening while under observation, although there 
is no sperm-nucleus in either 4 or c. At in fig. 1 is seen a 
small unipolar mass containing two sperm-nuclei ; the apex of 
this mass was twitching when the drawing was made. But it 
must be remembered that as a rule no motion is seen except in 
the tails of perfect spermatozoa; so that when I say that the 
protoplasm is the active agent in separating the spermatozoa 
from the larger masses, I mean that it does so in the same 
