Part 3

3. Wood market at Laghouat. Roots of Zizyphus, branches of juniper and pine, and pine bark. The latter is said to be used for staining.

Pl. 2, fig. 4. Shoot-habit of Acanthyllis tragacanthoides. Laghouat.

5. Shoot-habit of Zollikoferia spinosa. Laghouat.

6. Acanthyllis tragacanthoides on sandy plain. Laghouat.

7. Zollikoferia spinosa in habitat, plain (hamada). Laghouat.

Pl. 3, fig. 8. Detail of north slope of Nomad Mountains, where Zollikoferia spinosa is the dominant species. Laghouat.

9. Vegetation of plain (hamada) at Tilrempt. The conspicuous shrub is Haloxylon articulatum.

10. The daya of Tilrempt from the plain, showing the character of the depression.

Pl. 4, fig. 11. Near view of the daya of Tilrempt. The fortified stage station, bordj, and a nomad camp are to be seen. The flattened, level, lower surface of the trees is the effect of grazing, mainly by camels.

12. Jujube (Zizyphus) shrubs and betoum (Pistacia) at the daya of Tilrempt.

Pl. 5, fig. 13. A young specimen of betoum in the midst of a protecting jujube at the daya of Tilrempt.

14. Leaf and shoot habit of the jujube (Zizyphus lotus). Daya of Tilrempt.

15. Leaves of the betoum (Pistacia atlantica) from the daya of Tilrempt.

Pl. 6, fig. 16. South wall of the valley of the Oued M’Zab at Ghardaia.

17. Detail of an eroded bank of the Oued M’Zab at Ghardaia. The overhanging stratum is hardpan similar to the “caliche” of southwestern United States.

Pl. 7, fig. 18. Shoot-habit of Haloxylon articulatum, from the plain near the daya of Tilrempt.

19. Agriculture at Ghardaia. The fields are divided into plots about 3 by 4 feet in size, for the more economical use of water. Young barley is shown growing (November).

Pl. 8, fig. 20. Vegetation in upper part of a “draw” on plain north of the M’Zab Valley, Ghardaia.

21. Situation of square No. 2, on plain north of valley at Ghardaia.

Pl. 9, fig. 22. Capparis spinosa at base of valley wall at Ghardaia.

23. Leaves of Capparis spinosa from Ghardaia.

Pl. 10, fig. 24. Leaf-habit of Dæmia cordata. Ghardaia.

25. Shoot-habit of Salvia ægyptica. Ghardaia.

26. Upper surface of rocks, showing small incrusting lichens, on a low mountain about 5 km. north of M’Zab Valley, Ghardaia.

Pl. 11, fig. 27. Habitat of Peganum harmala, at Melika, Ghardaia.

28. Shoot and leaf habit of Peganum harmala, from Ghardaia.

Pl. 12, fig. 29. Habit of Henophyton deserti at Ghardaia when growing in a protected situation (cemetery).

30. Leaf-habit of Henophyton deserti. Ghardaia.