1/4 



THE GERM-CELLS 



of the ensuing division-spindle. They seem, however, to have no 

 part in the formation of the mitotic fic^ure or in division, and both 



Fig 88. -Formation of the spermatozoids in the vascular crvptogams. MarsiUa (.-1 D 

 R^'w^ttf-^'"'^'' • '^' ^' ^"•''^■'>' (^y»u>o^ram,„e (//-A", BeLAJF.FF), and Equisetum (L-N, 



.-/. Primary spermatogonium (two generations before the primary spermatocytes) in diyision 

 showing centrosomes. B. Primary spermatocyte with pair of " blepharoplastoids " (centrosomes).' 

 C. i^pindle of primary spermatocyte (f^rst maturation-division). D. Four of the eight secondary 

 spermatocytes w,th blepharoplast. Z^-^ Prophase of second maturation-division. H Pair of 

 spermatids (Gymno^^ram,„e) with blepharoplasts. /-J. Formation of the ciliated bandVrom the 

 Dlepnaroplast A. Nearly ripe spermatozoid, showing ciliated band {b), nucleus, and "cyto- 

 plasmic vesicle (the latter is ultimately cast off). E M. Spermatids of Equisetum. N Ripe 

 spermatozoid from above, showing spiral ciliated band. O. Ripe spermatozoid of MarsiUa with 

 very long spiral ciliated band. ". wm 



