838 



jr. W. DAW80N ON A SPECIMEN OF DIPLOXVLON 



proatest diameter, and consists of a central pith cylinder and tv^o con- 

 centric coats of scalarit'orm tissue (fig. 3), The pith cylinder is replaced 

 by sandstone, and is about one centimetre in diameter. The inner 



p- 2. Jjonffitudirud and Tratisvei'se Sections of the, Trunh, sJiowhuj 



*hp rmition of the Axis. (Scale 2* feet to 1 inch. Drawn by 



the postt 

 Mr. Hill.) 



a, a, a. Internal axis. 



cylinder of 83alariform tissue is perfectly continuous, not radiated, 

 and about one millimetre in thickness. Its vessels are somewhat 

 crushed; but have been of large diameter. Its outer surface, which 



I 



'■^4 



