APPENDIX. NOTES ON THE GEOLOGY OF SYRIA,

(Kindly communicated to me by my friend, Professor Edward Forbes.)

My Dear Sir,—It is much to be desired that a careful geological exploration of your interesting country should be undertaken by an able investigator. All that we know of the structure of Syria is fragmentary, and in great part unsatisfactory. Sufficient, however, is known to indicate the scientific importance of the region, and to hold out a promise of a rich harvest for the practical geologist who may undertake its description. The collection of fossils which I have myself seen from the district around Lebanon, suggested many enquiries that have not yet been answered, especially respecting the relations of the jurassic and cretaceous rocks of that famous region. The following scanty notices of what is known about Syrian formations and their fossils, may serve to excite curiosity and to direct the traveller to fresh observations.

In the year 1833, a valuable memoir by M. Botta, Jun., was published by the Geological Society of France. It is entitled “Observations sur le Liban et l’Antiliban.” He represents Mount Lebanon as composed of rocks belonging to the lower cretaceous series, resting upon green sands, and these in their turn reposing upon jurassic strata. He states, that in the chain of the Lebanon there are three distinct formations. The uppermost is a limestone, very variable in character, both of appearance and hardness, and alternating with calcareous marls. The lower division of this formation is distinguished by the presence of beds and nodules of flint. Fossil sea-urchins occur in its middle, and fishes in its lower part. A second formation of variable thickness is sandy, very ferruginous, abounding in iron ores and lignites, and passing above into a calcareous rock. The lowest formation is constituted of numerous beds of cavernous limestone. Besides these older rocks, M. Botta remarks upon the presence, all along the coast from Beyrout to Tripoli, of conglomerates or sandstones, quite unconformable to the calcareous rocks of the coast.

M. Botta takes particular notice of those localities in which remarkable fossils occur. The first is at the bottom of the basin in which Antoura is built. The stratum is confused marl, abounding in specimens of sea-urchins. These species are remarkable for their size and shape. He considers this bed as belonging to the jurassic series. Corals are also found in it.

The second locality is near the convent of Bikeurby, where a stratum occurs containing numerous univalve shells of the genus Nerinœa, which being harder than the rock containing them, stand up on its weathered surface.

The third locality is at Sach el Aalma, where at about 300 feet above the level of the sea occurs an impure limestone, often soft. In it fossil fishes are found in plenty. They are irregularly disposed in the rock.

The fossil fishes of Mount Lebanon have been the subject of frequent investigations, although the true geological position of the beds whence they are derived, has not yet been made out with certainty. Two memoirs have especially been devoted to descriptions of them, the one by M. Heckel (1843), and the other by Professor Pictet, of Geneva (1853). Professor Agassiz also has written upon some of the Lebanon fishes, and Sir Philip Grey Egerton has described a very remarkable fossil, viz., the Cyclobatis Oligodactylus, brought from Syria by Captain Graves, R.N., who kindly committed it to my care in 1845. Altogether no fewer than thirty-four fossil fishes from Mount Lebanon are now known and described. As the works in which the accounts are contained are not likely to pass into the hands of travellers, it may be useful to give a list of some of the principal of these very interesting and beautiful fossils.

Of the family of perched fishes there occurs a species of Beryx, a genus of which certain fossil forms are found in the chalk, and a few living species in the Indian seas. The Beryx Vexillifer is found in the hard limestones of Hakel.

Of the family of sparoid fishes, one or two species occur in the soft limestones of Sach el Aalma. The Pagellus Libanicus is an example.

Of the family of Chromidæ, three species of Pycnosterinx occur in the soft limestones of Sach el Aalma, viz., P. discoides, P. Heckelii, and P. Russegerii.

Of the Squamipennes, a Platax occurs in the hard limestones of Hakel.

Of the Cataphracti, a new genus called Petalopteryx has been established by Pictet for a fish from Sach el Aalma. Of the Sphyrenoid fishes, a Mesogaster occurs at the same locality. To the Halecoid fishes a great number of those of Lebanon belong; among them are the following:—

Osmeroides Megapterus, Sach el Aalma.

Eurypholis (new genus of Pictet) sulcidens, from Hakel.

Eurypholis Boisseri, from the same locality.

Eurypholis longiden, from Sach el Aalma.

Spaniodon (new genus of Pictet) Blondelii, from Sach el Aalma.

Spaniodon elongatus, Sach el Aalma.

Clupea lata, Sach el Aalma.

Clupea macropthalma, Hakel.

Clupea sardiniodes, Hakel.

Clupea laticauda, Hakel.

Clupea minima, Sach el Aalma.

Clupea brevissima, Hakel. This fish, originally described by M. de Blainville, appears to be very common in its locality.

Of the Esocidæ, there is the fish called Rhinellus furcatus, which occurs at Sach el Aalma.

Of the Sclerodermi, several species of Dircetis occur at Sach el Aalma. A curious and anomalous fish, called Coccodus armatus, is found at Hakel.

Of Cartilaginous fishes, a Spinax is found at Sach el Aalma.

The curious Cyclobatis oligodactylus of Egerton belongs to the same division.

In the north of Syria, M. C. Gaillardot has observed several distinct stages of rocks belonging to the great Nummulitic formation, and therefore, according to the received geological classification, members of the Eocene group of Tertiaries. The newest of these beds are stated to consist of compact white or grey limestones containing fossil corals, sea-urchins, and oysters. Under these is a white chalky limestone, alternating with green and grey soft marls and other limestones, almost entirely made up, according to Vicomte D’Archiac, of the Nummulina intermedia. In the white limestones of Ainzarka are found Nummulina Raymondi, N. lœvigata, and Alveolina subpyrenacia. M. Gaillardot would distinguish the entire group of strata constituting the highest mountains of Syria by the name of the Libanian System. He appears, however, to have confounded strata of very different ages, tertiary rocks with cretaceous and jurassic. In the true Lebanon region the mummulitic beds seem to be altogether wanting. It is possible that they may be present in the Antioch district, but this has not been clearly made out as yet. M. Russegger has shewn, contrary to the views of M. Gaillardot, that the region around Jerusalem is mainly of oolitic age, with occasional remains of cretaceous strata outlying here and there.

During the Armenian expedition to the shores of the Dead Sea, considerable collections of Syrian fossils appear to have been amassed. These have been described by Mr. Conrad, and are figured in the report very recently published by Mr. Lynch. The cretaceous beds of Syria are therein referred in part, at least, to the age of the white chalk of Europe. The Jurassic fossils are, for the most part, in the condition of casts. Species of Nerinœa were noticed, and among European forms, the Ostrea scapha of Roemer, and the Ostrea virgata of Goldfuss. A very remarkable fossil is the Ammonites Syriacus, from the Lebanon region; it is a species apparently of the genus Ceratites, a group of cephalopods usually regarded as characteristic of strata of Triassic age, but in this instance possibly represented among cretaceous beds.