Small WOOD. — Maturation Haminea. 



PLATE 13. 



All preparations stained witii iron lia;niatox>iin and Bordeaux red. 



Figs. 89, 90. Propliase of first cleavage. Tlie cleavage asters are not yet con- 

 nected witli eacli other, but are associated one with each pronucleus. 

 The chromatin of the chromosomes is solid (Fig. 89) or vesicular 

 (Fig. 90). Tlie rest of the cliromatin exists in the form of rings. 

 There is a thin layer of sphere-substance around each centrosonie. 

 X 1(380. 



Fig. 91. Telophase of first cleavage. Tiie chromosomes have fused into irregular 

 nuclei. The astral rays directed toward the disappearing centrosome. 

 X 1224. 



Fig. 92. Anaphase of first cleavage. Part of the chromosomes vesicular. Centro- 

 some still present, but irregular in outline. Thickenings on interzonal 

 filaments. X 1224. 



Fig. 93. Prophase of first cleavage. The solid black bodies are chromosomes. 

 The cytoplasm in the region of the deutoplasm takes a deep stain. 

 X 1680. 



Fig. 94. Centrosome, cut parallel to axis of spindle, composed of centriole and 

 centroplasm. Sphere-substance differentiated into medullary and cor- 

 tical layers. X 1680. 



Fig. 95. Composite figure, from three sections of the incompletely fused nuclear 

 vesicles derived from the ciiromosomes. First cleavage. X 2733. 



Fig. 96. Prophase of second cleavage. Cleavage asters independent of eacli other, 

 and lying at different levels in the section. X 1224. 



Fig. 97. Quiescent nuclei in two-cell stage. Interzonal filaments and midbodj 

 present. X 1224. 



Fig. 98. Prophase of third cleavage. Asters independent of each other. Cyto- 

 plasm takes a deep stain in region of deutoplasm. X 1224. 



