150 J- Moore, 



(Figs. 12, 13, 14 e 5'). It is moreover not difficult to find cells which 

 show these extra-nuclear chromatic particles in various stages of grou- 

 ping, from one of diiîusion throughout the cytoplasm to one of for- 

 mation of a localized clump beside the nucleus (Figs. 13, 14, 19, 20, 21 ch'). 

 The condensation thus produced continues to augment until it ultima- 

 tely appears as one large chromatic mass, in whose vicinity one or 

 two unfiised chromatic particles may still remain (Figs. 13, 14, 16, 19 he). 

 These changes seem to occur very quickly, and it is consequently, 

 difficult to obtain cells which show the actual transmigration of chro- 

 matin from the nucleus. 



If such figures as I have been able to collect are compared to- 

 gether it will be seen that, roughly speaking, there is an inverse ratio 

 between the stainability of the nucleus as a whole, and the size and 

 condensation of the extra nuclear chromatic mass which has (Figs. 12, 

 13, 14, 15 he) apparently passed from it. This extra-nuclear ehro- 

 matic hody is a large and conspicuous object in the spermatids of the 

 rat; indeed, in sections treated by the Fuchsin and Orange method, 

 it is by far the most intensely coloured object in the cell; and conse- 

 quently, the inverse ratio in the stainability referred to is very marked 

 indeed, — greatly more so than in relation to the chromatic body of 

 the previous cellular generation. If however we turn to other forms 

 (ex. the dog and cat) it will be seen that the chromatic body of the 

 corresponding generation presents, in comparison, a marked reduction 

 in size; indeed, variation of its characters seems to have been noted 

 by Benda in a short publication, „Ueber die Histiogenese des Saurop- 

 sidenspermatozoons" (Verhandlung d. Anaf. Gesellschaft. 1892. Bd. VI). 

 But we find also that, in different species, the inverse ratio between 

 the stainability of the nucleus and the chromatic body varies pro- 

 portionately to the size of the latter; this seems quite capricious in 

 its appearance and dimensions, similarity of character having little to 

 do with the mutual relationship of species. It would be quite easy 

 to arrange a series, beginning with rats and mice, passing, through 

 forms in which it becomes less and less conspicuous, to types like men 

 and bulls, in which I have not always been able to satisfy myself of 

 its existence. 



