PI. Ill 



I 



N 



Henriette Wilhelmina 



Beijerinck (1847-1937); 



elder sister of the scientist. 



Frederik Leonard Beijerinck 



(1844-1883); brother of the 



scientist. 



* > 



J 



i. 



Johanna Hermana Alida 



Beijerinck (1849-1923); 



younger sister of the 



scientist. 



M. W. Beijerinck as a student, at the 

 age of 20. 



