THE BACTHRIAL NUCLEUS 83 



the same procedure as in the case of plant and animal cells. Both members 

 oi the chromosome pairs are of equal value and one is transmuted to each 

 daughter cell. If more than one pair is present, half the nuclear complement 

 passes to each daughter cell, and each chromosome divides, becoming a pair 

 in the next generation. 



Cells in young, smooth cultures contain one pair, latterly tv^o pairs of 

 chromosomes. In older cultures the secondary nucleus, a central body, 

 single or double, is found. Alternatively, the nucleus adopts the form of a 

 longitudinal rod. The resting nucleus may arise from either of these nuclear 

 phases, by an autogamous or sexual process. 



Cells in rough bacilh contain a single pair of chromosomes w^hich fuse 

 to form a rod-shaped nucleus prior to sporulation. The entire complement 

 of four cells takes part in the fusion. 



Non-sporing, rough bacilli usually adopt the secondary nuclear condition 

 in older cultures, and each cell is separately transformed into a microcyst, 

 with or without sexual fusion. 



BIBLIOGRAPHY 



(i) Allen, L. A., Appleby, J. C. and Wolf, J. (1939) Zbl. f. Bakt. II. loo. 3. 



(2) Badian, J. (1930) Act. Soc. Bot. Pol. 7. 55. 



(3) Badian, J. (1933a) Arch, f Mikrobiol. 4. 409. 



(4) Badian, J. (1933b) Act. Soc. Bot. Pol. 10. 361. 



(5) BissET, K. A. (1947)]. Gen. Microbiol. 2. 83. 



(6) BissET, K. A. (i94Ha) ibid. 2. 126. 



(7) BissET, K. A. (1948b) ibid. 2. 248. 



(8) BissET, K. A. (i94Sc)J. Hyg., Camb. 46. I73- 



(9) BissET, K. A. (i94Sd) ibid. 46. 264. 



(10) BissET, K. A. (1949a) J. Gen. Microbiol. 3. 93. 



(11) BissET, K. A. (1949b) ibid. 3. App. ii. 



(12) BissET, K. A. (1949c) J. Hyg., Camb. 47. 182. 



(13) BissET, K. A. (1950)]. Gen. Microbiol. 4. i. 



(14) BissET, K. A. (1951) Cold Spring Harbor Symposia. 16. 373. 



(15) BissET, K. A. (1953a) Stain Technol. 28. 45. 



(16) BissET, K. A. (1953b) J. Gen. Microbiol. 8. 50. 



(17) BissET, K. A. (1954)]. Bact. 67. 41. 



(18) BissET, K. A. and Hale, C. M. F. (195 J- Hyg. 49- ^01. 



(19) BissET, K. A.. Grace, J. B. and Morris, E. O. (1951) Exp. Cell. Res. 3. 388. 



