MISSOURI 

 BOTANICAL. 



GARDEN. 



BULLETIN 



OF THE 



TORREY BOTANICAL CLUB 



Vol. XVII.] New York, May 9, 1890. [No. 5. 



Studies in Cell-division. 



1. 



By Douglas H. Camphei.l. 



(Plates.CII. and CIIL) 



The following paper was written, not so much as a contribu- 

 tion to our knowledge of the subject, as to call the attention of 

 teachers of botany to several characteristic and accessible exam- 

 ples for demonstrating easily the most essential points in this 

 very important subject. 



It is a common idea that the study of cell-division, especially 

 the division of the nucleus, is a very difficult subject for anyone 

 not thoroughly versed in histological methods, and while this is 

 in many cases true, nevertheless it is possible to find cases where 

 these processes can be readily studied with very little aid from 

 reagents, and indeed in some instances followed through in the 

 living cell. 



The last ten or fifteen years have seen a great advance in our 

 knowledge of these processes. Up to about 1875, in which year 

 the first edition of Strasburger's " Zellbildung und Zelltheilung " 

 appeared, the general belief current was that of Hofmeister, who 

 believed that in all cases of cell-division the nucleus first became 

 dissolved and that subsequently new nuclei were formed from the 

 cell-plasma previous to the division of the latter. Since the ap- 

 pearance of Strasburger's book the subject has attracted the at- 

 tention of many of the ablest zoologists as well as botanists, 

 among whom none have done more than Strasburger himself 



