368 TH. H. MONTGOMERY, The spermatogenesis of Peripatus. 



Fig. 260. Lateral view of first spermatocyte, begiuning of synapsis, 

 showing the grouping of the 4 daughter chromosomes into two bivalent 

 pairs ; each chromosome has broken up into its component granules, and 

 the latter are elongating preparatory to the longitudinal splitting. Con- 

 nective fibres still present, but the mantle fibres have disappeared. The 

 axial linin threads now visible, and the linin still in the form of a 

 continuous spirem. 



Fig. 261. Lateral view of spermatocyte in telophase or beginning 

 of rest stage. Chromosomes split longitudinally, linin spirem still per- 

 sistent. Secondary linin fibrils formed: these not colored in red, since 

 it could not be determined whether they are derivatives of the linin 

 spirem. The idiozome cap (Id.Z) and the Zwischenkörperchen-plate 

 (Z.K) shown in their regular position; they mark the distal pole of 

 the cell, while the opposite pole is the central jDole; both these poles 

 of the cell can be recognized with certainty from the stage of Fig. 259 

 to the stage of the 1st maturation monaster. 



Frommanusche Buchdruckerei (Uermann Pöble) in Jena, — 2136 



