78 GENERAL BOTANY 



and the beginning of telophase (7i). During their migration to the 

 poles the chromosomes assume various forms in the nuclei of 

 different plants and in those of the same plant in different kinds 

 of cells. In the root tip the chromosomes during anaphase are 

 usually greatly elongated and often hooked like a shepherd's 

 staff, while in the germ cells of the same plant they are more 

 often V-shaped and greatly shortened and thickened. In nuclei 

 in root tips the traction fibers appear to be attached to the bent 

 chromosomes at the curve of the hooked chromosomes, while in 

 the germ cells they are attached at the point of the V. It should 

 perhaps be stated that there is no evidence that the traction fibers 

 actually contract and pull the chromosomes to the poles, beyond 

 the facts of their apparent attachment and the peculiar appear- 

 ance of the chromosomes at this period, when they look like 

 plastic rods being pulled poleward. It is quite possible that the 

 chromosomes move to the poles by virtue of their own inherent 

 power of movement, or else by attraction exerted at the poles 

 during anaphase. 



The telophase (A, i) is the final phase of mitosis and includes the 

 organization of the daughter nuclei and the division of the cell 

 into two daughter cells. The formation of the daughter nuclei 

 occurs after the daughter star stage, which marks the close of 

 anaphase. The daughter chromosomes, in the stage immediately 

 following the daughter star arrangement, draw together and 

 adhere to form a dense mass of chromatin at either pole of the 

 nucleus. A new nuclear membrane is now formed around each 

 chromatin mass by the cytoplasm. Within each daughter nucleus 

 thus initiated a nuclear vacuole arises ; the chromatin mass be- 

 gins to loosen up, and the outlines of the daughter chromosomes 

 reappear. The chromosomes then begin to spread out and unite 

 by new anastomosing branches of their chromatin substance, while 

 vacuoles appear in increasing number within each chromosome. 

 By the formation of these vacuoles and new anastomosing branches 

 the chromosomes are soon reduced to the form of a network, or 

 meshwork, quite similar to that of an ordinary resting nucleus. 

 With the growth of the chromatin net the nuclear sap increases 

 in volume and apparently inflates the nuclear membrane, which 



