154 BOTANICAL GAZETTE Imarch 



2T0W 



metam 



;ytoplasin consequently gradually diminishes. The blepharo- 



round in shape, lies very 

 ^herical surface (figs, 2j. : 



(fig 



cross-section is crescent-shaped, the concave surface being in close 

 contact with the nuclear membrane (fig, 24). The elongation of the 

 blepharoplast now proceeds farther. Fig. 26 shows the section of the 

 blepharoplast at this stage, cut parallel with the axis of elongation. 

 The cross-section of the blepharoplast is shown in fig. 27, and a part 

 of the structure view^ed from the surface is given in fig. 25. 



Until this time the blepharoplast is alike at both ends, and no 

 modification was ever observed in the structure of the nucleus; but 

 soon after the blepharoplast has elongated into a semicircular band, a 

 very complicated modification follows in both nucleus and blepharo- 

 plast. One end of the blepharoplast becomes w^edge-shaped and 

 loosel} laid along the spherical surface of the nucleus (fig. 28), while 



the other end, which still remains pointed 



(figs.28.2gy The elon- 



gating blepharoplast now takes a spiral direction and has a tendency 



to form a coiled ribbon-like structure. 



WTiile the foregoing modification is occurring in the blepharoplast, 

 the nucleus undergoes a characteristic transformation of form. The 

 distribution of the ragged chromatin clumps within the nucleus be- 

 comes irregular; at certam regions of the nuclear cavity they become 

 grouped very densely; while in other parts the chromatin substance 

 is scattered. The 

 seems to be easilv 



at this time, 

 occurs in the 



mtenor of the nucleus, so that the region where the chromatin clumps 

 are densely crowded may protrude above the spherical surface of the 

 nucleus, while the region with scanty chromatin material may forn 

 a depression or furrow. This unevenness in the form of the nucleus 

 brou^t about by the irregular aggregation of the ragged chromatir 

 clumps in different regions of the interior, develops in such a direc 

 tion that the nucleus becomes metamorphosed into a coiled structure 

 W hen the nucleus has almost assumed the coiled form, one end o: 



