Bl ackma.n. — Spermatogenesis of Scolopendra. 



PLATE 8.— Continued. 



Fig. 141. The nucleus in the early prophase. The karyosphere is giving origin 



to the first chromosome. 

 Fig. 142. Late stage in disintegration of karyosphere. The last chromosome is 



arising from this structure, leaving the accessory chromosome as a 



remnant. 

 Figs. 143, 144. Slightly earlier stage than that of Figure 142, showing the origin 



of the chromatin segments from the karyosphere. and the forms taken 



on by the chromosomes as they arise. 

 Fig. 145. Early metaphase of first spermatocyte, taken at such a focus as to 



give a general view of the spindle. 

 Fig. 146. Slightly later metaphase, showing centrosphere and centrosome. 

 Fig. 147. Portion of the same cell showing the spindle. The spindle has begun 



to undergo its rotation, and all of it does not appear in one section. 



