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The Spermatogenesis of Bufo Lentiginosus 
EXPLANATION OF FIGURES ON PLATES L-III. 
All figures were drawn with the aid of a camera lucida under a Zeiss apoc. 
1.5 mm., oc. 8. The following abbreviations are used in lettering the figures: 
F. C., follicle cells; A, acroblast; C, centrosome; Ac, acrosome; M. P., middle- 
piece. 
EXPLANATION OF PLATE I. 
Fig. 1. Resting primary spermatogonium surrounded by follicle cells. 
Fics. 2-3. Early prophase of mitosis in a primary spermatogonium. All 
24 chromosomes are shown. 
Fic. 4. Equatorial section of the spindle in a primary spermatogonium 
during metakinesis. 
Fic. 5. Longitudinal section of the spindle in a primary spermatogonium 
during metakinesis. 
Fic. 6. A secondary spermatogonium during the resting stage. 
Fic. 7. Early prophase of mitosis in a secondary spermatogonium. 
Fic. 8. Longitudinal section of the spindle in a secondary spermatogonium 
during metakinesis. 
Fic. 9. Anaphase of mitosis in a secondary spermatogonium. 
Fic. 10. Young primary spermatocyte before the formation of the nuclear 
reticulum. 
Fies. 11-14. Growth stages of the primary spermatocytes. 
Fic. 15. The primary spermatocyte at the end of the growth stage. The 
nucleus contains a spireme that appears to be continuous. 
Fics. 16-21. Stages showing the gradual condensation of the chromatin 
that precedes synizesis. 
Fig. 22. Synizesis stage in the primary spermatocytes. The mass of 
chromatin is stained black with iron-hematoxylin. 
Fic. 23. Same stage as the preceding, showing the appearance of the mass 
of chromatin when the greater part of the iron-hematoxylin has been 
extracted. 
Fias. 24-25. Post-synizesis stages in the primary spermatocytes. The 
chromatin is being evolved in the form of a continuous spireme. 
