No. 5.] STRUCTURE IN AN ABNORMAL PIGEON. 



221 



to believe that such conditions are brought about by both divi- 

 sion and fusion. The greatest amount of doubling was seen 

 in the very young ova, and, I think, resulted generally from 

 division. Although no actual division was observed, yet the 

 general appearance of the cytoplasm, and n. 

 the plump, full nuclei of the young double 

 eggs, exhibited none of the signs of 

 deterioration one would expect if a fusion 

 of two eggs, preparatory to going to 

 pieces, were in progress. Some of the 

 smaller eggs are doubtful, however, and 

 the indications are that there may be 

 fusion instead of division. There can 

 be but little doubt that a form, such as 

 is shown in Fig. 8, is the result of a fusion. 

 By following out the serial sections, it was found to be really 

 two ova with a single nucleus which resulted from the fusion 

 of the two original nuclei. The nucleus thus formed seemed 

 to be almost completely degenerated, and was wholly devoid of 



Fig. 8. — x 525. A double egg 

 formed by fusion. The two 

 nuclei have united to form 

 one. The follicle has dis- 

 appeared. «, nucleus; s, 

 sphere. 



Fig. 9. 



Fig. 10. 



Fig. 9. — X 525. A double nucleated cell. _/, follicle ; «, nucleus ; s, sphere. 

 Fig. 10. — X 525. A triple nucleated cell. 



contents beyond a few rough, straggling threads of poorly stain- 

 ing material. The follicle had disappeared. Figs. 9 and 10 are 

 two rather doubtful cases. In each the follicle was repre- 

 sented by a few large cells irregularly disposed, but whether 



