PLATE LIX 
Fig. x .—Log from collection of woods in the Forest-Products Laboratory—a speci¬ 
men of the material used in this study; 5 , sapwood; H, heartwood. 
Fig. 2.—Specimens of woods showing creosote penetrance in sap and heartwood 
as affected by tyloses. The three specimens each contain both sapwood and heart- 
wood. Specimen A.—Red oak. Has no tyloses; creosote passed chiefly down the 
large vessels; note black streaks. Wood substance between vessels little treated; 
note white streaks. Specimen B .—White oak. Has abundant tyloses in sap and 
heartwood. Creosote penetrated the sapwood only. Thorough absorption obtained 
in the sapwood substance between the impenetrable, tylose-filled vessels. Speci¬ 
men C.—Pignut hickory. Has abundant tyloses in sap and heartwood. Creosote 
penetrated both. Good absorption throughout in the wood substance between the 
tylose-filled vessels. Compare Plate LI I, figure i, an enlarged view of a portion of 
this block. 
28736°—14-3 
