shiny, and of a deep chocolate brown color. In very narrow-ringed wood and in inferior red oak it is usually much reduced in quantity as well as quality. The pith rays of the oak, unlike those of the coniferous woods, are at least in part very large and conspicuous. (See Fig. 4; their height indicated by the letter _a_, and their width by the letter _b_.) The large medullary rays of oak are often twenty and more cells wide, and several hundred cell rows in height, which amount commonly to one or more inches. These large rays are conspicuous on all sections. They appear as long, sharp, grayish lines on the cross-sections; as short, thick lines, tapering at each end, on the tangential or "bastard" face, and as broad, shiny bands, "the mirrors," on the radial section. In addition to these coarse rays, there is also a large number of small pith rays, which can be seen only when magnified. On the whole, the pith rays form a much larger part of the wood than might be supposed. In specimens of good white oak it has been found that they form about sixteen to twenty-five per cent of the wood. [Illustration: Fig. 7. Portion of the Firm Bodies of Fibres with Two Cells of a Small Pith Ray _mr_ (Highly Magnified).] [Illustration: Fig. 8. Isolated Fibres and Cells, _a_, four cells of wood, parenchyma; _b_, two cells from a pith ray; _c_, a single joint or cell of a vessel, the openings _x_ leading into its upper and lower neighbors; _d_, tracheid; _e_, wood fibre proper.] Minute Structure [Illustration: Fig. 9. Cross-section of Basswood (Magnified). _v_, vessels; _mr_, pith rays.]