What is a mass or ball of cells formed by the repeated division of a male germinal cell (spermospore), each constituent cell (spermoblast) of which is converted into a spermatozoid; a spermatogemma called?

spermosphere — A mass or ball of cells formed by the repeated division of a male germinal cell (spermospore), each constituent cell (spermoblast) of which is converted into a spermatozoid; a spermatogemma. (Webster's 1913.)

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