158 LOUISE 15. WALLACE. 



EXPLANATION OF PLATE III. 



FIGS. 38, 39. Secondary spermatocytes. Late anaphase. 



FIGS. 40, 41. Secondary spermatocytes. Telophase. Accessory chromosomes 

 large and conspicuous. 



FIGS. 42, 43. Spermatids. Axial filament grows out from centrosome. 



FIGS. 44, 45. Spermatids. Interzonal fibers disappear. The mid-body persists 

 at center of "connecting-body." 



FIGS. 46, 47. Spermatids. Contraction stage. Accessory chromosomes sur- 

 rounded by clear area. 



FIGS. 48, 49. Spermatids. Accessory chromosomes unite and pass toward cen- 

 tral pole ; proximal centrosome passes over or into nucleus. Axial filament lengthens. 



FIGS. 50, 51. Spermatids. Nucleus elongated. Accessory chromosomes again 

 show partial separation. Chromatin plate forms. Proximal centrosomes becomes 

 larger. 



FIG. 5 2 - Spermatid. Cross-section of accessory chromosomes. Chromatin plate 

 and proximal centrosome. 



FIGS. 53, 54. Spermatozoa. Apical granule projects from apical body. Proxi- 

 mal centrosome becomes end-knob. Accessory chromosomes on convex side of head 

 in Fig. 53. 



