tributaries rise in the Majerda and Aures mountains. Flowing north-east the Majerda forms an extensive plain in its lower course, reaching the sea near the ruins of Utica. Vegetation is abundant, and recalls that of the more fertile districts of southern Spain and of Italy. On the higher mountains the flora has a very English character, though the actual species of plants may not be the same.
2. The central plateau region, stretching between the Majerda valley and the mountains of Gafsa. The average elevation of this country is about 2000 ft. The climate, therefore, in parts is exceedingly cold and bleak in winter, and as it is very wind-swept and patched in summer by the terrible qibli or “sirocco” it is much less attractive in appearance than the favoured region on the northern littoral. Although it is almost always covered with some kind of vegetation, trees are relatively rare. A few of the higher mountains have the Aleppo pine and the juniper; elsewhere only an infrequent wild terebinth is to be seen. In these two regions the date palm is never met with growing naturally wild. Its presence is always due to its having been planted by man at some time or another, and therefore it is never seen far from human habitations. These central uplands of Tunisia in an uncultivated State are covered with alfa or esparto grass; but they also grow considerable amounts of cereals—wheat in the north, barley in the south. The range of the Saharan Atlas of Algeria divides (roughly speaking) into two at the Tunisian frontier. One branch extends northwards up this frontier and north-eastwards across the central Tunisian table-land, and the other continues south-eastwards between Gafsa and the salt lakes of the Jerīd. The greatest altitudes of the whole of Tunisia are attained on this central table-land, where Mt Sidi Ali bu Musin ascends to about 5700 ft. About 30 m. south of the city of Tunis is the picturesque mountain of Zaghwan, approximately 4000 ft. in altitude, and from whose perennial springs comes the water-supply of Tunis to-day as it did in the time of the Carthaginians and Romans. North-east of Zaghwan, and nearer Tunis, is the Jebel Resās, or Mountain of Lead, the height of which is just under 4000 ft.
3. The Sahel. This well-known Arab term for coast-belt (which in the lural form reappears as the familiar “Swahili” of Zanzibar) is applied to a third division of Tunisia, viz. the littoral region stretching from the Gulf of Hammamet to the south of Sfax. It is a region varying from 30 to 60 m. in breadth, fairly well watered and fertile. In a less marked way this fertile coast region is continued southwards in an ever-narrowing belt to the Tripolitan frontier. This region is relatively flat, in some districts slightly marshy, but the water oozing from the soil is often brackish, and in places large shallow salt lakes are formed. Quite close to the sea, all along the coast from Hammamet to Sfax, there are great fertility and much cultivation; but a little distance inland the country has a rather wild and desolate aspect, though it is nowhere a desert until the latitude of Sfax has been passed.
4. The Tunisian Sahara. This occupies the whole of the southern division of Tunisia, but although desert predominates, it is by no means all desert. At the south-eastern extremity of Tunisia there is a clump of mountainous country, the wind-and-water-worn fragments of an ancient plateau, which for convenience may be styled the Matmata table-land. Here altitudes of over 3000 ft. are reached in places, and in all the upper parts of this table-land there is fairly abundant vegetation, grass and herbage with low junipers, but with no pine trees. Fairly high mountains (in places verging on 4000 ft.) are found between Gafsa and the salt lakes of the Jerīd.
These salt lakes are a very curious feature. They stretch with only two short breaks in a line from the Mediterranean at the Gulf of Gabes to the Algerian frontier, which they penetrate for a considerable distance. They are called by the French (with their usual inaccuracy of pronunciation and spelling) “chotts”; the word should really be the Arabic shat, an Arab term for a broad canal, an estuary or lake. These shats however are, strictly speaking, not lakes at all at the present day. They are smooth depressed areas (in the case of the largest, the Shat el Jerīd, lying a few feet below the level of the Mediterranean), which for more than half the year are expanses of dried mud covered with a thick incrustation of white or grey salt. This salt covering gives them The Shats. at a distance the appearance of big sheets of water. During the winter, however, when the effect of the rare winter rains is felt, there may actually be 3 or 4 ft. of water in these shats, which by liquefying the mud makes them perfectly impassable. Otherwise, for about seven months of the year they can be crossed on foot or on horseback. It would seem probable that at one time these shats (at any rate the Shat el Jerīd) were an inlet of the Mediterranean, which by the elevation of a narrow strip of land on the Gulf of Gabes has been cut off from them. It is, however, a region of past volcanic activity, and these salt depressions may be due to that cause. Man is probably the principal agent at the present day in causing these shats to be without water. All round these salt lakes there are numerous springs, gushing from the sandy hillocks. Almost all these springs are at a very hot temperature, often at boiling point. Some of them are charged with salt, others are perfectly fresh and sweet, though boiling hot. So abundant is their volume that in several places they form actual ever-flowing rivers. Only for the intervention of man these rivers would at all times find their way into the adjoining depressions, which they would maintain as lakes of water. But for a long period past the freshwater streams (which predominate) have been used for irrigation to such a degree that very little of the precious water is allowed to run to waste into the lake basins; so that these latter receive only a few salt streams, which deposit on their surface the salt they contain and then evaporate. This abundant supply of fresh warm water maintains oases of extraordinary luxuriance in a country where rain falls very rarely. Perennial streams of the description referred to are found, between the Algerian frontier and Gabes on the coast. The town at Gabes itself is on the fringe of a splendid oasis, which is maintained by the water of an ever-running stream emptying itself into the sea at Gabes after a course of not more than 20 m.
All this region round the shats has been called the “Jerīd” from the time of the Arab occupation. “Jerīd” means in Arabic a “palm frond” and inferentially “a palm grove.” The fame of this Belad-el-Jerīd, or “Country of the Date Palms,” was so exaggerated The Jerīd.during the 17th and 18th centuries that the European geographers extended the designation from this small area in the south of Tunisia to cover much of inner Africa. With this country of Jerīd may be included the island of Jerba, which lies close to the coast of Tunisia in the Gulf of Gabes. The present writer believes that the date palm was really indigenous to this district of the Jerīd, as it is to countries of similar description in southern Morocco, southern Algeria, parts of the Tripolitaine, Egypt, Mesopotamia, southern Persia and north-western India; but that north of the latitude of the Jerīd the date did not grow naturally in Mauretania, just as it was foreign to all parts of Europe, in which, as in true North Africa, its presence is due to the hand of man. To some extent it may be said that true North Africa lies to the north of the Jerīd country, which, besides its Saharan, Arabian and Persian affinities, has a touch about it of real Africa, some such touch as may be observed in the valley of the Jordan. In the oases of the Jerīd are found several species of tropical African mammals and two or three of Senegalese birds, and the vegetation seems to have as much affinity with tropical Africa as with Europe. In fact, the country between the Matmata highlands and the strait separating Jerba from the mainland is singularly African in the character and aspect of its flora. To the south of the Jerīd the country is mainly desert—vast unexplored tracts of shifting sand, with rare oases. Nevertheless, all this southern district of Tunisia bears evidence of once having been subject to a heavy rainfall, which scooped out deep valleys in the original table-land, and has justified the present existence of immense watercourses—watercourses which are still, near their origin, favoured with a little water.
Hot and mineral springs may be almost said to constitute one of the specialities of Tunisia. They offered a singular attraction to the Romans, and their presence in remote parts of the country no doubt was often the principal cause of Roman settlement. Even at the presentMineral Springs. day their value is much appreciated by the natives, who continue to bathe in the mined Roman baths. The principal mineral springs of medicinal value are those of Korbus and Hammam Lif (of remarkable efficacy in rheumatic and syphilitic affections and certain skin diseases), of the Jerīd and Gafsa, of El Hamma, near Gabes, and of various sites in the Kroumir country.
Climate.—The rainfall in the first geographical division is pretty constant, and may reach a yearly average of about 22 in. Over the second and third divisions the rainfall is less constant, and its yearly average may not exceed 17 in. The mean annual temperature at Susa is 75° F., the mean of the winter or rainy season 60° and of the hot season 97°. At Tunis the temperature rarely exceeds 90°, except with a wind from the Sahara. The prevailing winds from May to September are east and north-east and during the rest of the year north-west and east. A rainy season of about two months usually begins in January; the spring season of verdure is over in May; summer ends in October with the first rains. Violent winds are common at both equinoxes. In the Tunisian Sahara rain is most uncertain. Occasionally two or three years may pass without any rainfall; then may come floods after a heavy downfall of a few weeks. Perhaps if an average could be struck it would amount to 9 or 10 in. per annum.
[Geology.—The greater part of Tunisia is composed of sandstones, marls and loosely stratified deposits belonging to the Pliocene and Quaternary periods. The oldest strata, consisting of gypsiferous marls, are referred to the Muschelkalk and show an alternation of lagoon with marine conditions. The Lias and Oolite formations are well represented, but the Sequanian and Kimmeridgian subdivisions are absent. Lower Cretaceous rocks, consisting of thick limestones, shales and marls, occur in Central Tunisia. The fossils show many notable affinities with those in the Lower Cretaceous of the Pyrenees. Limestones and marls represent the stages Cenomanian to Upper Senonian. The fossils of the Cenomanian have affinities with those in the Cenomanian of Spain, Egypt;
Madagascar, Mozambique and India. The Senonian consists of a
