10 FOOT. [VoL. XII. 
of the sperm produces the centre of activity, around which 
the archoplasm (a/ready present in the egg) aggregates.1 In 
the egg of Allolobophora foetida this blue archoplasmic mass ts 
so pronounced that there can be no question as to its individuality , 
zt 1s as distinct as the cytoplasmic network itself, thus supporting 
Bovert’s assertion of the specific character of archoplasm. 
In this figure (Fig. 10), drawn from preparations fixed in 
chromo-acetic, we find not only the centrosome but the red 
anastomosing rays of the attraction-spheres sharply defined. 
At the stage represented in Fig. 11 most of the archoplasm 
(especially in chromo-acetic preparations) is aggregated at the 
periphery of the egg, only a relatively small amount being 
present around the very small male and female pronuclei; but 
in corrosive acetic preparations the archoplasm is not limited 
so nearly to the periphery, some masses being present through- 
out the cytoplasm of the egg. This presence of the polar-ring 
substance on the periphery of the egg, prior to its aggregation 
at the poles, supports Vejdovsky’s? observations on Rhynchelmis. 
Fig. 12 represents the stage at which both pronuclei are 
formed, a large part of the archoplasm having aggregated at the 
two poles of the egg, thus forming the polar rings. In addition 
to the archoplasm at the poles, a relatively large amount has 
aggregated around the pronuclei (one of which is shown in the 
figure); and at the points where the membrane is breaking 
down the archoplasm is entering into the pronucleus itself. 
The archoplasm massed around the pronuclei has a different 
1In the relatively large spermatozoa of Amphiuma (which the kindness of 
Professor Conklin has enabled me to study), I have obtained a reaction to Lyon’s 
blue both in the middle-piece and in the tail. The red cytoplasm and the blue 
archoplasm are present in both structures, suggesting that the apparent absence 
of the archoplasm in the spermatozoén of AJlolobophora foetida may be due to 
faulty technique. I think, however, there can be no question that the relatively 
large amount of archoplasm in the cone and attraction-spheres of the egg of 
Allolobophora foetida is merely an aggregation of the archoplasm already 
present in the egg. This conclusion is in accord with the observations of Wheeler 
on the egg of AZyzostoma, in which he finds the archoplasm of the cleavage 
attraction-spheres furnished by the egg alone. Wm. M. Wheeler, “The Behavior 
of the Centrosome in the Fertilized Egg of Myzostoma glabrum Leuckart.” 
JOURNAL OF MORPHOLOGY, vol. X, 1895. 
2 F. Vejdovsky, “ Entwicklungsgeschichtliche Untersuchungen.” Tafs. IV und 
V, Prag, 1892. 
