List of Plates 



I. Martinus Willem Beijerinck Frontispiece 



From the bronze plaque by Professor A. W. M. Ode. 



II. Ancestors of M. W. Beijerinck page 4 



Martinus Beijerinck (1718-1782) ; great-grandfather of the scientist. 



Frederik Beijerinck (1766-1838) ; grandfather of the scientist. 



Derk Beijerinck ( 1 805- 1879); father of the scientist. 



Jeannette Henriette van Slogteren (181 1-1875) ; mother of the scientist. 



III. M. W. Beijerinck, his brother and his sisters in their youth . . page 1 2 

 Frederik Leonard Beijerinck (1844-1883); brother of the scientist. 

 Henriette Wilhelmina Beijerinck (1847-1937) ; elder sister of the scientist. 

 Johanna Hermana Alida Beijerinck (1849-1923) ; younger sister of the scientist. 

 M. W. Beijerinck as a student, at the age of 20. 



IV. Facsimile of title page of Beijerinck's thesis for the degree of Doctor of 

 Science page 15 



V. Beijerinck in the prime ot his life, at the age of 45 page 24 



VI. Four prominent collaborators of Beijerinck during his academic period 



page 25 

 A. H. van Delden. -- G. van Iterson Jr. - - H. C. Jacobsen. N. L. Sohngen. 



VII. Beijerinck shortly before his retirement from the chair at Delft, at the 



age of 70 page 36 



VIII. Beijerinck's country-home at Gorssel (province of Gelderlancl) after a 



water-colour by his sister, Miss H. W. Beijerinck page 40 



IX. Beijerinck in his garden at Gorssel, at the age of 73. --Beijerinck with 



his sister and their household companion in 1929 page 42 



X. Facsimile of part of a letter from Beijerinck to one of his collaborators 



(1924). . page 44 



XI. Facsimile of the testimonial accompanying the Emil Christian Hansen 



Medal, conferred on Beijerinck in 1922 page 46 



XII. Facsimile of a page of Beijerinck's laboratory note-book (May 22nd 

 June 1st, 1887), giving his first observations on the root nodule bacteria 



page 106 



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

 1900). Here the name Azotobacter cliroococcum is used for the first time 



page 140 



