258 



EggNvxdeus 

 Centrosewe, 



CONKLIN. 



FIGS, i and 2. Prophase and Metaphase of First Cleavage. S.N. = Sperm Nucleus. 

 Ch. = Chromosomes. S. = Sphere. C. = Centrosome. 



9 Nude 



Lobq 



FIGS. 3 and 4. Anaphase and Telophase of First Cleavage, showing dual nuclei, centrosomes 

 (C)and spheres (S), " Zwischenkorper" (/.), bending of spindle axis, and progressive absorp- 

 tion of yolk lobe. 



FIGS. 5 and 6. Prophase of Second Cleavage, showing dual nuclei with central spindle tying in 

 groove between the halves ; Fig. 5 viewed from one side, Fig. 6 from animal pole. The 

 sphere's (S) lie over the nuclei and immediately under the cell wall ; the spindle axis is bent 

 on itself, and the "Zwischenkorper" (Z) is carried nearly to the vegetal pole; the nuclei 

 shows processes projecting toward the " Zwischenkorper," and the yolk lobe (L) is almost 

 completely absorbed. 



