PI. XIII 



6 



* 



e 

 ' 





O 



<\ 

 <^ 







r*, 



5 



" 



y , 



, 



' ( 



jfa/Lk s*A 



^> 



.*.- 



>/ 









Facsimile of a page of Beijerinck's laboratory note-book (Dec. 3 1st, 1900). 

 Here the name Azotobacter chroococcum is used for the first time. 



