NOTES ON KARYOEINESIS. 



By L. B. ELLIOTT. 



So little comparatively is known of the process of cell- 

 division in the plants of our region that the following notes 

 may be of interest. 



The karyokinetic figures described by Strasburger and 

 others are found in great abundance in the dividing nuclei of 

 the mother cells of Botrychiinn virginianum, Schwz. Since 

 the process of division is one of very short duration it is not 

 always possible to select a specimen of just the right age; but 

 by taking those of the fertile fronds which are just unrolling 

 it is reasonably certain that somewhere the cells will be found 

 in the right condition. 



After thoroughly hardening by soaking in alcohol, at first 

 weak, then increased to the full strength, the pinnte should be 

 picked off and placed in a mixture of equal parts, alcohol and 

 ether, for forty -eight hours, after which celloidin may be 

 added. As the celloidin slowly dissolves, the spaces between 

 the now somewhat shrunken mother-cells and the wall of the 

 young sporangium will become filled. Thin sections can then 

 be cut and the cells will not drop out and be lost. 



Much time may be saved by mounting several pinnfe flat 

 on the same cork. A section from this mount will give all 

 the characters of several pinnae at once. 



The youngest cells will be found, of course, in the pinnae at 

 the end of the frond and in the sporangia at the end of the 

 pinna. 



