67 



TISSUE OF FIBRES. 



WHILE the tissue of cells just described, may be 

 said to resemble the flesh of plants, the tissue of fibres 1 , 

 may be said to resemble the bones, though plants have 

 not anything exactly corresponding to animal bones. 

 The fibres are not always interior like bones, but are 

 found in bark ; and to this, indeed, grasses and other 

 slender plants owe their stiffness. A good example 

 of the tissue of fibres may be seen in the bark of flax 

 and hemp, which is the part made into cloth and 

 cordage. Du Hamel fancied these fibres could be 

 divided into finer and finer ones without end ; but the 

 smallest are only about one sixth less than that of a 

 human hair. 



All the fibres are tapering, transparent, and allow 

 fluids either to pass through them or between them. 

 They are not composed of cells, as some erroneously 

 state. 



This tissue composes all the woody part of plants 

 and trees, and is found of course in the ribs of the 

 leaves. 



The Straight Vessels. 



It appears to me that what I have just described as 

 fibrous tissue, has been frequently termed the straight 

 vessels, of which various accounts are given. 



Grew describes these as straight hollow threadlets., 



(i; Jn Latin, Tela fibrosa ; inaccurately, Vasafibrom. 



