N O ^ 



P 



R S T 



Fig. 135. — Diagrams illustrating diiferenl accounts of reduction in the flowering plants. 



A-D, Vegetative mitoses (heterotypical form) in Picea. [Bei.ajeff.] 



E-/. Illustrate Strasburger's earlier account (95) and the later one of Guignard, of the first 

 maturation-division. E. Doubly split rod. F. Metaphase, in profile. G. The same e?i face, 

 showing the heterotype ring. H. I. Opening out and breaking apart of the ring. 



J-M. Later account of Strasburger and Mottier {cf. Figs. 133, 134). J. Longitudinally split, 

 V-shaped chromosome of first division. K. Opening out of the ring. L. Prophase of second 

 division, showing longitudinally split segmented spireme. M. Initial anaphase of second division. 



K-Q. First division. [Belajeff.] N. Longitudinally split chromosomes, viewed in the equa- 

 torial plane. O. The same viewed in the axis of the spindle. P. Separation of the daughter- 

 chromosomes. Q. Anaphase, all the chromosomes assuming the V-form. 



R-T. Second division in //■«. [Bei.ajeff.] R. Equatorial plate, limbs of X's and V's break- 

 ing apart (reducing division). .S. Slightly later stage, with daughter-chromosomes still united at 

 one end. T. Anaphase. 



270 



