PLATE XXVII.— TANGENTIAL SECTIONS OF TRANSVERSE RESIN DUCTS. 



J-C, PiNUS T/EDA. n iiiid /•,', V. i'Ai,li.STKl8. /'', P. ECiiiNATA. <1, P. iiETKitoi'ii vi.i.A. r. (L, resin limits; Ir., trans- 

 verse trachcids; 2>t l>arrnchyiiia. 

 Magnilifiition of originals, ^'f; of illustrations, ^1"^. 



156 



