[096]

Appearances presented by longitudinal and transverse sections of recent and fossil Coniferous woods, cut into thin slices, and magnified 400 times. (Nicol.)

Fig. l. Longitudinal Section of Pinus Strobus, cut parallel to a medullary ray.

Fig. 2. Transverse Section of the same.

a. a. Portions of concentric annual layers.

Fig. 3. Longitudinal Section of Araucaria Cunninghami.

Fig. 4. Transverse Section of the same. [097]

Fig. 5. Longitudinal Sections of Araucaria excelsa, shewing polygonal disks, in double and triple rows, on the surface of the longitudinal tubes. Some of the tubes are without disks, as in all Coniferæ.

Fig. 6. Transverse Section of Araucaria excelsa.
a. Portion of concentric annual layer.

Fig. 7. Radiating and concentric structure of a branch of Pinus, as seen by the naked eye in a transverse section; the microscopic reticulations are omitted. (See V. I. p. 486. Note.)

a. a. Concentric annual layers, indicating periodical growth.

Fig. 8. Longitudinal Section of Pinus, shewing the relative positions of the longitudinal vessels and medullary rays.
a, Longitudinal vessels, forming the woody fibres.
b, Medullary rays.