68 



EISEN. 



[Vol. XVII. 



Formation of twenty-four leaders in the polymorphous sper- 

 matogonia. 



Somatic mitosis of the same. 



Formation of twelve leaders in the auxocytes. 



Longitudinal splitting of the spireme segments or leaders. 

















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£• 



Figs. a.-^. represent a broken series of leaders illustrating the formation of the leader and the 

 chromosome, a. — Isolated row of chromioles surrounded by chromoplasm and suspended 

 in a network of linosomes; B. — Chromoplast with twelve leaders of chromioles. From 

 the imperfect resting stage of the polymorphous spermatogonium ; c. — Chromoplast with 

 five leaders. Each leader is made up of chromoraeres, and each chromomere consists of 

 three or more chromioles surrounded by chromoplasm. A network of linosomes between 

 the chromomeres ; d. — Three chromomeres, each with six chromioles surrounded by a 

 chromoplasm and suspended in a network of linosomes ; e. — A bretzel chromosome con- 

 taining chromioles and two chromoplasts with endochromatic granules ; _/. — A chromo- 

 some from the metaphase. It contains thirty-six chromioles and a terminal chromoplast 

 with an endochromatic granule ; ^. — Part of a chromosome from the spermatocyte . 



Contraction of the separated halves of the leaders into chro- 

 mosomes. 



Equation division of the chromosomes by heterotypic mitosis. 

 Confluence of the chromosomes. 



