H Doc 181 



Plate XXI) 



m.r. 



\m\\\\r 



W3Wm&m$M ' 



kvWonrt K^^noV iLCMJLl W 1 1 AjML 



««^^«t-5m 



Radial Sections of Pinus echinvta and heterophylla 



A and .5, Pinls echinata m? medullary ra>s, p paienclrvma ol same ft tians»\eise ttatheids of lays sp simple pits frp,boideied 



pits, c h common tiacheids 

 C, Pinus hfterophylla. su u summeiwood othei letters as m 4 

 Originals magnified 5 T Q , lllusti ations -$° 



