âÔ ITHOS. H. MONTGOMERt jt., 



being the generally accepted terminology proposed by v. la Valette 

 St. George and Boverl There is a long lapse of time (marked by 

 a correspondingly long zone in the testicle) between the metaphases 

 of the last generation of spermatogonia and the prophases of the 

 1st spermatocytic division. Within this period falls the growth period 

 of the cell, more especially in the final stages of the anaphase, in 

 the telophase and in the rest. We may consider separately these 

 three stages. 



a) The anaphase. 

 From the stage of spermatogonic metakinesis until the complete 

 separation of the daughter cells (and when in each of the latter a 

 nuclear membrane has been acquired), has been termed by me the 

 metaphase of the spermatogonia; and the period from this stage up 

 to the telophase, the anaphase. The anaphase itself may be subdivided 

 into 3 well marked periods: the early anaphase, the synapsis, and 

 the postsynapsis. 



The early anaphase. 

 The 14 chromosomes found in each daughter cell (1st spermatocyte) 

 of the last division of spermatogonia (Figs. 46, 47) lie at first scat- 

 tered at one pont in the cell body, around which a nuclear membrane 

 soon makes its appearance; this is the beginning of the anaphase 

 (Figs. 48—50). The chromosomes are then irregularly grouped in the 

 large, clear nuclear cavity ; few strands of linin are found in the nucleus 

 at this period, though remnants of the spindle fibres (mantle fibres) 

 converge from the chromosomes through the nuclear membrane to a 

 point in the cytoplasm where the centrosome probably lies, though I 

 have been unable to detect the latter structure at this stage. These 

 persisting fibres will be referred to subsequently. The chromosomes 

 now stain purplish or nearly violet with Hermann's double stain, and 

 the intensity of the violet coloration continues from this stage on; 

 while in the metaphase, metakinesis and prophases (back to the loose 

 spirem stage) of the preceding division they stained red (with saiîranine). 

 This well-known staining reaction, first recognized (if I remember cor- 

 rectly) by Flemming, gives valuable aid in determining the first stages 

 of the anaphase. In each nucleus, from the commencement of the 

 anaphase on, one of the chromosomes still retains the red stain 

 characteristic of all of them in the immediately preceding period, and 

 this particular element (n. 2 of the figures) is destined to become the 

 chromatin-nucleolus, the metamorphosis of which will be described later. 



