PROCESS OF FERTILIZATION IN THE CRAB 181 
10. The wall of the capsule, together with its everted contents, 
which we now call the sperm-vesicle, sinks into the cytoplasm 
of the egg, where it is enlarged and transformed into the male 
pronucleus. 
11. The contents of the capsule may be derived from the 
nucleus of the spermatid and is probably oxychromatin which 
deposits basichromatin after it enters the egg and so gives rise 
to the chromosomes in the male pronucleus. 
