482 FOOT. [ VOL.) 13%, 
guishing characteristics of male or female pronuclei, either 
in size, shape or chemical reaction. Each contains the net- 
work, chromatin, and from one to seven nucleoli. The nucleoli 
persist during the cleavage spindle, but how much later, I am 
unable at present to state. 
Polar rings (Figs. 7, 8).— Whitman (7) in 1878 published 
a detailed description of the dark areas at the two poles 
Fic. 7. Optical section of entire egg. Polar bodies divided into eight pieces. 
Polar-rings at opposite poles. Male and female pronuclei near center of egg. 
of the egg of Clepsine, known as the polar rings. At that 
time he predicted that the “clear spot’”’ described by Kowalev- 
sky in Rhynchelmis, and interpreted as the germinal vesicle, 
would be found to be a polar ring. Vejdovsky (6) verified this 
prediction in 1892. I have found similar formations in the 
egg of Allolobophora foetida, appearing at opposite poles and 
attaining the maximum of their development at the time the 
pronuclei are formed. Figs. 7 and 8, show the form and size 
of the average rings. They are on the extreme periphery of 
