Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/119

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Wady Bader. One Echinoderm, Heterodiadema Libycum, Agass. et Desor, sp., was noticed to afford some evidence of the zone of Hippurites in Sinai ; and now Dr. Le Neve Foster in his section (cf. Tih) points out the existence there of Hippurites ; and Mr. Bauerman's collection contains some from Wady Nagh el Bader. The propriety of the assertion that a Turonian as well as a Cenomanian chalk existed in Sinai is therefore to be admitted. Mr. Bauerman and his colleagues have added by direct observation a higher stage to that previously known to exist amongst the Cretaceous series in the west of the Sinaitic peninsula. There are slight evidences of the existence of a chalk over the Hippurite -limestone ; but this must be stratigraphically the base of the white chalk of North-western Europe.

No fossils are in the collection now under consideration, nor were there any in Mr. Holland's, pointing to a Neocomian, Gault, or Upper Chalk horizon (chalk with flints).

A study of M. Coquand's 'Geologie et Paleontologie de la Region sud de la province de Constantine' (1862), and the examination of a collection of Algerian fossils in the possession of John Wickham Flower, Esq., F.G.S., place the affinities and distribution of the Sinaitic Cretaceous fossils in a very definite relation with those of the following etages : —

1. Rhotomagien, 2. Mornassien, 3. Provencien, 4. Santonien?

The Rhotomagien is the African zone of : —

Ammonites Mantelli, Sow. — — rhotomagensis, Brongn. — — varians, Sow.

Scaphites aequalis. Sow. Turrilites costatus, Lam. Pecten asper, Lam.

It contains a considerable number of Echinodermata and Ostreae ; and the commonest of these are found in Mr. Bauerman's collection.

Coquand's Carentonien (the zone of Aspidiscus cristatus, Lam. sp.), has not been traced in the Sinaitic chalk, nor has his Angoumien series ; but the Mornassien, the zone of the Echinodermata par exccellence, immediately beneath the zone of Hippurites cornu vaccinum, and the Caprotinas (the Provencien) are well represented there. The Provencien is distinguished in the present collection by the Caprotinas.

The following is a list of the species found by Mr. Bauerman, with their localities in Sinai, Algeria, Europe, and in other parts : —

1. Discoidea subuculus, Klein. Tih: Rhotomagien, Upper Greensand. 2. - Forgemolli, H. Coquand. Tih : Rhotomagien. 3. Epiaster distinctus, Agass. Wady Nagh el Bader : Zone of Pecten asper and N.E. Arabia. 4. - tumidus, Desor. W. N. B. : Cenomanien, France. 5. Periaster oblongus, D'Orb. W. N. B., Tih: Cenomanien, France. 6. Hemiaster Cenomanensis, Cotteau. Tih, W. F., W. N. B. : Cenomanien, France; Bagh. 7. Phymosoma Delamarrei, Desor. W. N. B. : Mornassien. 8. Pseudodiadema variolare, Brongn., sp. W. N. B., Tih: Upper Greensand, Red Rock.

  • W. N. B. = Wady Nagh el Bader. W. F. = Wady Ferran.