28 



THE STRUCTURE OF CELLS 



dumb -bell -shaped body, and finally two rows of granules are seen 

 to occupy the margins of the flattened linin riband. 



This stage is often (Salamander, Helix, Lilium, etc.) followed by 

 a more or less complete longitudinal fission and separation of the 

 linin riband, each half now containing, at least at first, a single row 

 of chromatin granules. It is perhaps not improbable that a similar 

 process also occurs during the corresponding stage of somatic 



1 



Fio. 14. 



Lilium martagon, prophase of the first mitosis in the pollen-mother-cell, showing the longi- 

 tudinal fission of the chromatin and linin. 



mitoses, but the shortness of its duration in the latter renders the 

 process difficult to observe. At or about this period a remarkable 

 contraction of the chromatic linin filament occurs, and commonly 

 the nucleolus is included in the tangle. To this stage the name of 

 Synapsis (Moore) has been given, and it seems to represent an 

 important step in the process, and one which is confined to this 

 first (heterotype) reduction division. After the synaptic condition 

 is over, the linin, which has been getting richer in chromatin, is 

 usually seen to be shortening, and at the same time thickening, but 



