PRELIMINARY NOTE ON THE MATURATION 
AND FERTILIZATION OF THE EGG OF ALLO- 
LOBOPHORAGPOERTIDA. 
KATHARINE FOOT. 
In the following preliminary I shall state briefly some of 
the results obtained from the study of more than two hundred 
eggs, taken from the cocoons of Allolobophora foetida, and 
supplemented by the study of the earlier stages in the ovary. 
The work was begun in the summer of 1893 at the Marine 
Biological Laboratory, Wood’s Holl, Mass. 
I express my grateful acknowledgments to the Director, 
Dr. Whitman, for his valuable assistance, and also to Dr. 
Conklin, a member of the staff. 
The deposition of the cocoons, which I have been so fortu- 
nate as to observe several times, will be fully described in a 
future paper. 
The shape of the average egg is shown in Fig. 1. The size 
at this stage of development varies from .10 mm to .15 mm, 
and the membrane adheres much closer to the egg than is the 
case after the polar bodies are formed. When the cocoon is 
first laid neither polar body has been constricted off; the first 
maturation spindle is formed, but still occupies the centre of 
the egg. As it approaches the periphery it occupies positions 
varying from perfectly radial to entirely tangential, but at the 
time of division it is either radial or slightly oblique. At each 
pole of the spindle there is a very pronounced aster. 
The spermatozoa are free in the albumen of the cocoon, and 
they do not penetrate the egg until some minutes (about ten) 
after the cocoon has been deposited. Fig. 2 shows an average 
spermatozoon obtained about two hours before the cocoon was 
laid. The full grown spermatozoon, taken from the freshly 
deposited cocoon, is about two and one-half times the length of 
the young sperm represented in the figure; thus the sperm 
grows with extreme rapidity during this interval of time. 
