Dec, 1906.] THE VICTORIAN NATURALIST. 145 



A PHYSIOLOGIST OF THE 17TH CENTURY. 



By Profssor Alfred J. Ewart, D.Sc, Ph.D., F.L.S., Govern- 

 ment Botanist. 

 {Read before the Field Naturalists' Qluh of Victoria, \Wi Nov., 1906.) 



In Sachs's masterly sketch of the history of botany from ancient 

 to modern times, full justice is done to Nehemiah Grew's 

 researches in phytotomy and vegetable histology ; and it is, 

 moreover, shown that Schleiden's accusation ( " Grundziige d. 

 Botanik," 1845, ^-j P* 207) was entirely unjust and unfounded, 

 for Grew was not merely Malpighi's contemporary but in many 

 ways his superior. Besides being a careful observer and an 

 accurate and painstaking draughtsman. Grew also possessed in an 

 eminent degree the power of drawing logical conclusions from 

 the facts at his command, and this is especially noticeable in his 

 essays upon plant physiology, of which Sachs makes almost no 

 mention. It is the purpose of the following note to show that 

 Grew is certainly to be regarded as one of the foremost founders 

 of experimental and deductive plant physiology, for many facts, 

 ideas, and theories which are supposed to be of comparatively 

 recent origin were first propounded or established by him. 

 The mere mention of a few of the more important of these will 

 suffice to indicate the permanent value of Grew's physiological 

 work. 



Thus (book i., p. 25)*:— "Of the lignous body it is so 

 apparent by its Pores, or rather by its vessels, that we need no 

 further evidence. For to what end are vessels but for the con- 

 veyance of Liquor ? And is that also, which upon cutting the 

 young Branch of a sappy Tree or Herb, by an accurate and steady 

 view may be observed. But when I say the Vessels of the 

 Lignous Body I mean principally them of the younger shootings, 

 both those which make the new Ring and those which are 

 mixed with the Cortical Body in the Barque." It seems 

 probable that by the vessels of the cortex Grew refers to sieve 

 tubes, for he distinctly states that they are completely filled with 

 watery contents ; but it is also possible that he is referring to 

 sclerenchyma fibres. Grew recognizes the fact that the rapid 

 ascent of water occurs in the young spring wood, although the 

 vessels may be largely filled with air, and evidently supposes 

 that both capillarity and imbibition aid in the process, for experi- 

 ments are mentioned upon the ascent of coloured fluids through 

 fibres of cotton and in capillary glass .tubes. 



It is distinctly stated in the introduction (p. t,'^) that the main 

 function of the leaves is to aid in the ascent of sap and to prepare 



* The whole of Grew's reseaixhes are contained in " The Anatomy of 

 Plants," published in 1682 (London), although many of the separate works 

 were published ten years before. 



