The following are the divisions which we have recognized* : —
MIDDLE CRETACEOUS.
1st. Gault, with Amm. Velledoe, Beudanti, mammillaris, Roissyanus, versicostatus, and Solarium ornatum.
2nd. Rhotomagian stage, with Amm. Mantelli, varians, rhotomagensis, Scaphites oequalis, and Turrilites costatus.
3rd. Carentonian stage. Base with Ostrea Flabellata ; upper part with Inoceramus labiatus, Pseudodiadema libycum, and Ammonites Woolgari (Mant.). (Lower chalk, Ligerian stage, Coq.).
4th. Angoumian stage, with Radiolites lombricalis and cornupastoris.
5th. Mornasian stage, marly, with Amm. Requienianus, and Trigonia scabra.
6th. Provencian stage, with Hippurites organisans.
This middle chalk is very admirably developed in the environs of Tebessa, and in the neighbouring Tunisia, as well as in the environs of Batna.
UPPER CRETACEOUS.
1st. Santonian stage, with Ostrea auricularis, Ostrea acutirostris, Lima Hoperi, Ostrea proboscidea D'Arch., Ostrea hippopodium, Ostrea santonensis, and Micraster cor-anguinum.
2nd. Campanian stage, with Ostrea vesicularis, Ostrea pyrenaica, Leym., Ostrea larva, Ammonites texanus, Rom., and Inoceramus Crispii, Mant.
3rd. Dordonian stage, with Radiolites Jouanneti, and Hippurites radiosus, Desml.
These divisions correspond exactly to those which we have met with in Lower Provence†.
When we consider that the long series of fossils described as peculiar to Algeria, and belonging exclusively to the middle and to the upper cretaceous, has been collected by only a few individuals, we shall readily understand that future researches must very extensively increase their number. Indeed, since the publication of my work
- Description Geologique et Paleontologique de la region sud de la Province
de Constantine, 1862.
† The author here gives a complete list of the species of fossils recognized by him as peculiar to the Algerian beds. These are arranged under their different stages, and their numbers are as follows : —
1. Gault 6 species 2. Rhotomagian 118 " 3. Carentonian 31 " 4. Mornasian 38 " 5. Provencian 10 " 6. Santonian 46 " 7. Campanian 22 " 8. Dordonian 5 " Total 276 "
As these species are cited from his work on the Geology and Palaeontology of the Province of Constantine, a list of their names would be equally useless to those who do, and to those who do not, possess that work.
