DEVELOPMENT OF THE GRAAFIAN FOLLICLE 399 



cell produces what may be termed a daughter ovum, together with 

 the first polar body, a minute cell of insignificant size. The second 

 mitosis is irregular in that the chromosomes separate without split- 

 ting, one-half going to the second polar body, the other to the 

 mature ovum, thus effecting the reduction of the chromosomes, a 

 deficiency which is compensated for in the event of fertilization 

 by the entry and. fusion of an equal number of chromosomes 

 derived from the male sperm nucleus of the spermatozoon. The 

 second mitosis may or may not be accompanied by mitotic division 

 of the first polar body; in the former case three, in the latter 

 only two polar bodies arise in connection with the process of 

 maturation of the ovum. 



DEVELOPMENT OF THE GKAAFIAN FOLLICLE 



The development of the Graafian follicle goes hand in hand 

 with that of the ovum and can be readily followed in ovaries from 

 individuals of different ages, children and adults, the mature fol- 



SV-H* 



FIG. 323. FUOM A SECTION OF THE OVARIAN CORTEX OF A NEW-BOBN KITTEN. 



jBT, Pfluger's tubes ; Ke, germinal epithelium ; w, mitosis ; Str, ovarian stroma ; Ub t 

 primitive follicles. Moderately magnified. (After Kolliker.) 



licles and corpora lutea appearing only after puberty. The process 

 begins in the germinal epithelium in which certain cells so increase 

 in size that they may be readily distinguished as future ova. More 



