Nigerian Eocene Mollusca. in 



and others are in favour of a Cretaceous horizon. Dr. Oppenheim 1 has 

 described older Tertiary shells, generally of small size, from the Cameroons, 

 while the same author 2 has fairly recently published a monograph on an 

 invertebrate fauna from the Togo limestones which he regards as resembling 

 that characterising the Ranikot Series of India and therefore of older 

 Eocene age. 



The late Prof. A. de Lapparent 3 was among the first authorities to 

 recognise the presence of Lutetian rocks in the Soudan area of Africa, while 

 Vasseur 4 was an early writer on Eocene Foraminifera from borings in the 

 kingdom of Senegal. Another monograph 5 of importance published in 1913, 

 deals with a series of Paleocene fossils from the Landana country of the 

 Belgian Congo, the Mollusca having been described by Dr. Em. Vincent, 

 the Chelonians by Prof. L. Dollo, and the Fish-remains by Prof. M. Leriche. 

 A later work on the Eocene of the Soudan and Senegal has been recently 

 issued by Prof. H. Douville" 6 ; it is descriptive of the Mollusca and Fora- 

 minifera which the author acknowledges as representing horizons ranging from 

 Paleocene to Upper Eocene times. 



Much information on the geology of the country between the Niger 

 and Lake Tchad is given in a work by Dr. G. Garde, 7 which should be 

 consulted by the student in connection with the discussions on the geological 

 age of the rocks forming the structure of that region, the author regarding 

 Eocene determinations of other palaeontologists as Upper Cretaceous. Prof. 

 H. Douville, however, has given an analytical review of this subject, and 



1 Uber Tertiarfossilien, wahrscheinlich eozanen Alters, von Kamerun : Beitr. Geol. Kamerun (Esch), 



1904, pis. 6-9, pp. 245-285. 



2 Die Eocane Invertebraten-Fauna des Kalksteins in Togo : Beitr. geol. Erf or. Deutsch. Schutzgeb., 



1915, part 12, pis. 1-5, p. 126. 



3 "Sur les traces de la Mer Lutetienne au Soudan," and "Sur de Nouveaux fossils du Soudan" 

 Compt. Rend., 1903, Vol. 136, pp. 1118 and 1297. 



4 Sur la decouverte du terrain nummulitique dans un sondage execute' a Saint-Louis du Senegal : 

 Compt. Rend., 1892, Vol. 134, pp. 60-63. 



5 Materiaux pour la Paleontologie du Bas-et du Moyen-Congo : Ann. Mus. Congo Beige, 1913, 

 Ser. 3, Vol. i, Fasc. i, p. 92, pis. i-io. 



6 L'Eocene au Soudan et au Senegal : Bull. Com. Etud. Hist. Afrique Occid. frangaise, 1920, 

 pp. 113-171, pis. 1-5. 



7 Description Geologique des Regions situees entre Le Niger et le Tchad (Paris), 1911, pp. 284, 

 maps, and one plate of fossil shells from the Adar-Doutchi Beds, which are referred to the 

 Maestrichtian zone of the Upper Cretaceous series. 



