41 8 EDWIN G. CONKLIN. 



EXPLANATION OF PLATE I. 



FIG. i. No. 1174(2). 37, J hr., during second maturation; then kept at room 

 temperature (ca. 27) for 3 hrs. The first polar body is shaded by transverse 

 lines; the sperm nucleus is shown at the left; the other nuclei are karyomeres 

 formed by the scattering of chromosomes of the second maturation mitosis. 



FIG. 2. No. 1175(2). 33, J hr., during first cleavage; room temperature 

 (ca. 27) 3 hrs. The imperfect fusion of the karyomeres (gonomeres?) gives an 

 appearance of amitosis to each of the nuclei. 



FIG. 3. No. 1176(2). 34-35, \ hr., during second cleavage; room tempera- 

 ture (ca. 23) 3 hrs. Karyomeres formed by scattering of chromosomes of second 

 cleavage. 



FIG. 4. No. 1173(2). 37, | hr., beginning of third cleavage; room tempera- 

 ture (ca. 27) 3 hrs. Many karyomeres formed by scattering of chromosomes of 

 third cleavage. Traces of centrospheres are shown in the cells. 



FIG. 5. No. 1176(2). 34-3 5, | hr., during third cleavage; room temperature 

 (ca. 23) 3 hrs. Karyomeres formed by scattering of chromosomes of third cleav- 

 age. In one quadrant a micromere was formed, in the other quadrants cell division 

 was suppressed. Traces of centrospheres as in preceding. 



FIG. 6. No. 1173(2). 37, \ hr., during anaphase of third cleavage; room 

 temperature (ca. 27) 3 hrs. In two quadrants micromeres have formed. Daugh- 

 ter nuclei are elongated in the greater dimensions of the chromosome plates, the 

 latter having fused together into irregular masses. 



