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INTRODUCTION TO CYTOLOGY 



Fig. 119. — Spermatogenesis in Marchantia. h, blepharoplast; c, centrosome; n, nucleus. 



{After Ikeno, 1903.) 





Fig. 120. — Spermatogenesis in Polytrichum. A-D, mitosis in androgones, showing 

 appearance of plastid material (k). E-H, behavior of centrosome in last division; each 

 androcyte (spermatid) has one centrosome, which acts as a blepharoplast {b). I-K, 

 transformation of androcyte into spermatozoid: a, apical body; I, limosphere; n, nucleus; 

 p, percnosome. L, mature biciliate spermatozoid. {After C. E. Allen, 1912, 1917a.) 



