Divisions in Vicia Faba. 
*53 
Summary. 
1. There are fourteen chromosomes in the sporophyte and seven 
in the gametophyte of Vicia Faba. 
2. On reaching the pole of the spindle the chromosomes become 
massed together and come into contact one with another. 
When this aggregation loosens, the chromosomes remain laterally 
attached to their neighbours and show longitudinal fission. 
The fission persists and is pulled out in the regions of the cross 
attachments to form the diamond-shaped meshes of the reticulum. The 
ends of the chromosomes also unite, and one or two nucleoli appear. Thus 
the * resting stage ’ is produced. 
3. On the initiation of a new division the cross attachments break down, 
the sides of the diamond-shaped areas approximate, and a double spireme 
is formed; this ultimately breaks transversely into longitudinally split 
chromosomes. 
4. The line of separation of the daughter chromosomes on the spindle 
is therefore marked out in the preceding telophase, and persists throughout 
the intervening stages. 
5. The chromosomes are frequently constricted into segments, and 
it seems probable that the way in which the segments are grouped to form 
chromosomes may vary. An explanation here suggests itself of the often 
recorded variation in the chromosome number, and possibly also of the 
Mendelian phenomenon of coupling. 
Bibliography. 
1. Digby, L. (’10) : The Somatic, Premeiotic, and Meiotic Divisions of Galtonia candicans. Ann. 
Bot., vol. xxiv, p. 727. 
2. Farmer, J. B., and Moore, J. E. S. (’05): On the Meiotic Phase (Reduction Division) in 
Animals and Plants. Quarterly Journal of Microscopical Science, vol. xlviii, p. 489. 
3. Farmer, J. B., and Shove, D. (’05) : On the Structure and Development of the Somatic and 
Heterotype Chromosomes of Tradescantia Virginica. Quarterly Journal of Microscopical 
Science, vol. xlviii, p. 559. 
4. Fraser, H. C. I., and Welsford, E. J. (’08): Further Contributions to the Cytology of the 
Ascomycetes. Ann. Bot., vol. xxii, p. 465. 
5. Gregoire, V. (’06): L’EHment chromosomique dans les cellules vegetales. La Cellule, 
vol. xxiii, 2 e fasc., p. 311. 
6. Gregoire, V., and Wygaerts, A. (’04): Reconstruction du noyau et formation des chromo¬ 
somes dans les cineses somatiques. La Cellule, vol. xxi, p. 1. 
7. Hof, A. C., (’98): Histologische Studien an Vegetationspunkten. Botanisches Centralblatt, 
vol. lxxvi, p. 221. 
8. Kemp, H. P. (’10) : On the Question of the Occurrence and Heterotypical Reduction in Somatic 
Cells. Ann. Bot., vol. xxiv, p. 775. 
