What is a primitive seminal cell, occuring in masses in the seminal tubules. It divides into a mass (spermosphere) of small cells (spermoblast), which in turn give rise to spermatozoids called?

spermatogonium — A primitive seminal cell, occuring in masses in the seminal tubules. It divides into a mass (spermosphere) of small cells (spermoblast), which in turn give rise to spermatozoids. (Webster's 1913.)

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