PLATE XXIV. RADIAL AND TANGENTIAL SECTIONS. 



A and B, PINUS TA;DA. Radial sections; m. r., medullary rays; (?., tracheids; p., ]>arencbyiua of the rays; s. p., 



simple pit; b. ]i., bordered pit; c. (/., common tracheids. 

 C-E, tangential sections. 



'', Pixrs I'Ai.usTRls. Left-hand part in spriugwood, right-hand portion in sunimerwood. 



D-K, Pixus KCHINATA. 7), Section in spriugwood; a-c, medullary rays; a, a small ray composed of tracheids only; 

 c, a "triple" ray; d, bordered pit showing the membrane in place. E, Section in summerwood; . bordi-rrd 

 pit, other letters as in A and 11. 



Magnification of originals, ^P; of illustrations: A and B, *$">; C-E, a ? Q . 

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