434 



HISTOLOGY 



At the same time an equatorial band of darker material appears in the 

 cytoplasm surrounding the nucleus (Fig. 386, d.m.}; this band is cut at 



two points and the sections 

 appear as two roughly 

 crescentic lines of some 

 width and tapering to 

 blunt points. The chro- 

 matic material has mostly 

 left the nucleus and been 

 added to the chromatin 

 particles which have now 

 become larger, more uni- 

 form in size, and are 

 evidently the future chro- 

 mosomes of the first reduc- 

 tion divisions. They 

 appear in the next stage 

 represented (Fig. 387) in 



FIG. 388. Anaphase of first reduction division in 

 Magnolia. X 1800. 



their regular size, shape, and arrangement, and the fibrils have been 

 arranged into the familiar spindle which here is gathered distally 

 into several points near together. The dark cytoplasm material is now 

 increased to form a complete shell about the whole figure which is just 

 beginning to divide its chromatin. 



Figure 388 shows the division half done, and again shows the differen- 

 tiation of mantle and spindle fibrils. The spindle fibrils seem to be fewer 

 in this stage than in a 

 later one (Fig. 389), 

 where they are very 

 numerous, and have 

 already begun to show 

 the equatorial plate that 

 marks the position of 

 the cell's final division. 

 The chromosomes are 

 still separate and are 

 somewhat fused. The 

 dark zone of cytoplasm 

 is diffused and shows 

 but a trace of its 



former presence. FIG. 389. Late anaphase of first reduction division in 



-n i . . ,., Magnolia. X 1800. 



Radiating aster-like 



rays reach from the chromosome masses out into the cytoplasm. 

 In Figure 390 the two nuclei are re-formed and have acquired a very 



