36 J. BRONTii GATENBY 



consists of two dictyosomes (' Nebenkern ' batonnets) ; but 

 in other cases there may be three, and one never finds a 

 spermatid with a single batonnet. It is therefore certain 

 that during dictyokinesis the Golgi elements are not always 

 sorted out equally. That the Golgi rod is divided or halved 

 like the chromosome is unlikely from this evidence, described 

 in detail elsewhere (9 «) : in Li max agrestis the spermato- 

 cyte has a Golgi apparatus formed of some eight dictyosomes 

 or batonnets. This cell divides twice to give rise to four 

 spermatids, ))ut each of the latter only contains two of the 

 Golgi batonnets ; this shows that in dictyokinesis the batonnet 

 is not divided like the chromosome.^ 



With regard to the fact of the maturation of the germ-cells 

 and the reduction of the chromosome number, nothing com- 

 parable can be found in either mitochondria or Golgi elements 

 of germ-cells. In the egg the polar bodies rarely contain mito- 

 chondrial granules or Golgi elements, and never in such 

 quantity as to suggest a special reduction in number. In the 

 case of the male germ-cells the same applies: the first and 

 second maturation divisions (chondriokinesis) in the male 

 are of the same type, and while they bring about a halving, 

 and then a rough quartering of the original number of mito- 

 chondria in the spermatocyte, this process is not of the same 

 nature as the reduction of the chromosomes. The same remark 

 applies to the Golgi elements in dictyokinesis of the male 

 germ-cells during maturation.^ 



In the last stages of gametogenesis in the male no chromosomes 

 are lost : the case of the mitochondria and Golgi apparatus is 

 instructive, for in many Mollusca it has been shown that 

 possibly all the Golgi elements, and much of the mitochondrial 

 matter, are lost during spermateleosis, being sloughed off the 

 tail of the sperm (9, 9 a). Such seems to occur with the mito- 

 chondria in Mammalia ; Eegaud shows that the bead of 

 sloughed off protoplasm of the sperm of rats may contain 

 mitochondria (24), though the main bulk of the granules 

 forms part of the sperm. In other words, the chromatin of the 



1 See also Ludford and Gatenby, ' Proc. Roy. Soe.', vol. 92, 1921. 



