issues the Macta. On the lower courses of the Habra and the
Sig, barrages have been built for irrigation purposes. The
Habra barrage holds 38,000,000 cubic metres; that on the Sig
18,000,000. The Tafna (about 100 m.) rises in a large cavern
in the mountains south of Tlemcen and flows N.E. to the sea at
Rachgun. It has many affluents; the largest, the Isser
(70 m.), joins it on the east bank about 30 m. above its
mouth. The Harrach (40 m.), a picturesque stream, enters
the Mediterranean in the Bay of Algiers. The Mazafran (50
m.) crosses the plains S.W of Algiers, reaching the sea N. of
Kolea. The Mejerda and its affluent the Mellegue, rivers
of Tunisia (q.v.), have their rise in Algeria, in the
mountainous country east of Constantine. None of these rivers is
navigable. Besides these there are a number of streams in the
interior, but they are usually dry except in the rainy season.
Algeria abounds in extensive salt lakes and marshes. Of
the lakes in the northern part of the country near the coast
the principal are,--the Fezara, 14 m. S.W. of Bona; Sebkha
and El Melah, south of Oran; and three small lakes in the
immediate vicinity of La Calle. In the high plateaus are
the Shat-el-Gharbi or Western Shat, the Shat-el-Shergui or
Eastern Shat, the Zarhez- Gharbi and the Zarhez-Shergui, the
Shat-el-Hodna and a number of others. South of the Jebel
Aures is another series of salt lakes closely connected with
the Shat-el-Jerid (of Tunisia). The chief of these is the
Shat Melrir. There are a number of warm mineral springs,
containing principally salts of lime, used with success
by both Arabs and Europeans in several kinds of disease.
One of the most remarkable groups of springs is near Guelma,
in the department of Constantine. There are two principal
sources. Their waters unite in one stream whose course is
marked by gigantic limestone cones, some of which are 36 ft.
high. The water, which is at boiling point, falls into
natural basins of a creamy white colour, formed by the deposit
of carbonate of lime. The springs are known to the Arabs
as Hammam Meskutin (the ``accursed baths''). The name and
the cones are accounted for by a legend which represents
that at this spot lived a sheikh who, finding his sister too
beautiful to be married to anyone else, determined to espouse
her himself. Whilst the marriage festivities were being
celebrated the judgment of Heaven descended on the guilty
pair; fire came from below; the water became hot and the
sheikh and his sister were turned into stone. Within a mile
of Hammam Meskutin are ferruginous and sulphureous springs.
[Geology.--The geology of Algeria has been worked out in
considerable detail by French geologists. Rocks of Archean
and Palaeozoic ages contribute only a small share, but there
is a very complete sequence of formations from the Lias to
those of recent date. An interesting and orderly petrological
sequence of Tertiary igneous rocks has been determined.
Archean rocks form the cores of the ancient crystalline masses
within the littoral zone from Algiers to Bona. They consist of
gneiss, mica-schist, quartzites, crystalline limestones and
conglomerates. Primary deposits are doubtfully represented
by the detached fragments of unfossiliferous strata of
Traras, Blida and east of Orleansville. Carboniferous and
Permian strata are possibly represented by some black and
grey micaceous shales with beds of coal in the Jurjura.
At Jebel-kahar and west of Traras, Pomel attributes certain
conglomerates, red sandstones and purple and green shales to
the Permian. The rocks of Secondary and Tertiary ages have
been profoundly affected by the Alpine movements, and are
thrown into a series of complex folds, so that in numerous
instances their stratigraphy is imperfectly understood.
The gypsiferous and saliferous marls of Shellata, Suk Ahras
and Ain Nussi have yielded Triassic fossils. Triassic
rocks are considered to be present in Constantine and in the
Jurjura. Rhaetic beds (Infra Lias), consisting of dolomites
and siliceous limestones, have been recognized at Saida.
The lower and middle divisions of the Jurassic, composed of
massive limestones more or less siliceous and overlain by
the marls and highly fossiliferous limestones of the Upper
Lias, play an important part in the constitution of the chief
mountains of the Tell. In south Oran they determine the
principal axes of the mountain ranges. The Inferior Cretaceous
rocks include the Neocomian and Gault (Albian and Aptian)
subdivisions, and form the flanks of the mountains in the
Tell. In the south the Albian subdivision of the Gault is alone
represented. Rocks of Upper Cretaceous age are represented
in all their stages. The Cenomanian presents two distinct
facies. North of the Atlas it belongs to the European type,
in the south it contains a fauna of oysters and sea-urchins
belonging to the facies ``africano-syrian'' of Zittel. There
is a continuous transition between the Senonian and Danian,
proving that the Algerian region did not participate in the
immersion which occurred in Provence and in the Corbieres
of southern France during the Danian epoch. The Lower Eocene
rocks contain the chief phosphatic deposits of Algeria, those
of the Tebessa region being the best known. Certain species
of nummulites, which are very common, distinguish the various
subdivisions of the Eocene. The highest beds, consisting of
quartzites, shales, marls and sandstones with the remains of
fucoids, are found in the Jurjura and Shellata. The Oligocene
period consists of a marine phase confined to the littoral
zone of Kahylia, and of a continental phase occupying vast
areas composed of lacustrine, alluvial, gypsiferous marls,
sandstones and conglomerates. The Miocene formation obtains
its greatest development in Oran and is much expanded in the
Tell. At the close of the Lower Miocene period (beds with
Ostrea crassissima) great modifications in the relief and
limits of the Algerian formations took place. Hitherto marine
conditions were confined to the littoral; in Middle Miocene
times (Helvetian) the sea broke in and spread in a south-east
direction in the form of long ramified fjords but did not
extend as far as the Sahara. To the Pliocene period the marine
deposits of the Sahel of Algiers and of the Sahel Jijelli
must be attributed; also the lacustrine marls and limestone
of the basin of Constantine, and the ancient alluviums of the
basins and depressions which bear no relation to the existing
valleys. Among the Tertiary volcanic rocks those of acid
types (granites, granulites) were the first to appear and
are developed latitudinally; rocks of intermediate type
(dacites, andesites) characterize the Miocene and early
Pliocene periods; while the basic rocks (ophites, elaeolite
syenites and basalts) attained their maximum in later Pliocene
and Quaternary times. Their development, feeble as compared
with the acid rocks, is meridional. The Quaternary period
includes an older stage containing fragments of fossils from
the underlying formations; a later stage containing the bones
of Hippopotamus, Elephas, Rhinoceros, Camelus, Equus;
and finally the vast accumulations of sand which began to
be formed in prehistoric times. The broad platforms of
the hamada are covered with Quaternary deposits. (W. G.*)]
CIimate.--Although Algeria enjoys a warm climate, the
temperature varies considerably in different parts, according
to the elevation and configuration of the country. Along
the coast the weather is very mild, the thermometer rarely
falling to freezing-point even in winter. The coldest month
is January, the hottest August. The mean annual temperature
in the coast plains is 66 deg. F. Heavy rains prevail from
December to March, and rain is not uncommon during other
months also, excepting June, July, August and September, which
are very hot and rainless. The average annual fall is 29
in. On the mountains and the high plateaus the winter is often
very severe; snow lies for six months on the higher peaks of
the Kabyle mountains. On the plateaus the temperature passes
from one extreme to the other, and rain seldom falls. (For
the climate of the Saharan region see SAHARA.) Throughout
Algeria, especially in the summer, there is a great difference
between day and night temperature, notably in the inland
districts. Between May and September the sirocco, or hot
wind of the desert, sweeps at intervals over the country,
impregnating the air with fine sand; but in general, with
the exception of the vicinity of the marshes, the climate is
healthy. Its salubrity has been increased by the draining
of many marshes in the neighbourhood of the larger towns.
Fauna and Flora.--The fauna of Algeria resembles that of
the Mediterranean system generally, though many animals once
common to South Europe and North Africa--such as the lion,
panther, hyena and jackal--are now extinct in Europe. Lions,
formerly plentiful, have disappeared, and leopards and panthers
are rare; but jackals, hyenas and Algerian apes are not
uncommon. Wild boars are found in the oak forests, and brown
bears in the uplands. In the south are various species of
antelope and wild goat. Red deer (Cervus elaphus barbarus),
which differ from the typical European species only in the
fact that the second tine is absent from their antlers, a
peculiarity which they share with the red deer of Spain and
Corsica, are still found in the forest of Beni Saleh in the
department of Constantine, but are being exterminated by forest
fires and poaching Arabs. Of domestic animals the camel and
sheep are the most important. The chief wealth of the Arab
tribes of the plateaus consists in their immense flocks of
sheep. The horses and mules of Algeria are noted; and the
native cattle are an excellent stock on which to graft the
better European varieties. Of birds, eagles, vultures, hawks,
owls and quails are common; snipe, curlews, plovers, storks
and herons frequent the marshy parts; and the ostrich the
desert. Partridges and woodcocks are fairly common. Among
the reptiles are various species of serpents, tortoises,
turtles, lizards, &c. Locusts are common and sometimes do great
damage. Scorpions are numerous in the acid regions. Algerian
prawns, especially those of Bona, are large and of a delicate
flavour. Of the twenty-one species of freshwater fish, five
are peculiar to the country, but none is of much economic
value save the barbel and eel. A species of trout is found
in the streams near Collo, but in none of the other rivers.
The flora of Algeria consists of about 3000 species, of which
some 450 are indigenous to the country, 100 being peculiar
to the Sahara. The flora of the Tell is South European in
character. The agave and prickly pear, the myrtle, the
olive and the dwarf palm grow luxuriantly; and the fields
are covered with narcissus, iris and other flowers of every
hue. Roses, geraniums, and the like, bloom throughout the
winter. The flora of the high plateaus consists chiefly of
grasses, notably various kinds of alfa or esparto, and aromatic
herbs. In the Saharan oases the characteristic tree is the
date palm--``the king of the desert.'' Over 11,000 sq. m. of
the mountainous country near the coast are covered with forests
of various species of oak, pine, fir, cedar, elm, ash, maple,
olive, many of them of gigantic size, and other trees; and on
the slopes of the mountains up to 3800 ft. above the sea the
fig is common. Its fruit forms one of the staple articles of
food among the Kabyles. Cork and carob trees are also very
