178 A. RICHARDS. 



EXPLANATION OF PLATE VIII. 



FIG. 61. Six cell stage. Next section shows seven chromosomes belonging to 

 this spindle. 



FIG. 62. Seven cell stage. Formol-sublimate, safranin and gentian violet. 



FIG. 63. Division in the eight cell stage, only one end of the spindle shown in 

 this section. Zenker, safranin and gentian violet. 



FIG. 64. From an embryo of about 30 cells, showing two mitoses. Zenker, 

 safranin and gentian violet. 



FIG. 65. A blastomere beginning mitosis from an embryo of 55 to 60 cells. Zen- 

 ker, safranin and gentian violet. 



