35G 



THE MICROSCOPE. 



t>ubject; and published cm excellent paper in the Micro- 

 scopical Socidys Transactions, 1840, which contains the 

 results of his observations. 



1 rig. 199. 



I, Interior cast of tlie siliceous portion of spiral tubes of the Opuntia. 2, Vertical 

 section of Elm, showing spiral fibre. 



Tn order to watch the development of the membranous 

 tubes of plants, no better example can be chosen than the 



Fig. 200. 



S A trsin.'jverse section of Taxus haccata (Yewl, showng the woody fibre 

 2, Vertical section of the Yew, exhibiting pores and spira.' fibres. 



