JURASSIC BIVALVIA AND GASTROPODA 

 FROM TANGANYIKA AND KENYA 



By L. R. COX 



CONTENTS 



I Introduction .......... 



II History of investigation of Jurassic Mollusca of East Africa 



III East African Jurassic bivalve and gastropod faunas and 



their characteristics ........ 



IV Systematic descriptions. ....... 



V List of fossil localities, with species collected from each . 



VI References .......... 



SYNOPSIS 



Page 

 4 

 5 



10 



25 



J 74 



198 



Jurassic Bivalvia and Gastropoda from Tanganyika and Kenya in the collections of the 

 British Museum (Natural History) are described in this memoir. The bulk of the material has 

 come from three sources, the British Museum East Africa Expeditions (1924-31), the Geological 

 Survey Departments of the two territories concerned, and the B.P.-Shell Petroleum Development 

 Company of Tanganyika, Ltd. 207 species of Bivalvia and 56 of Gastropoda are described, but 

 among them are 10 identified only generically and 12 of which the specific identifications have 

 been qualified or queried. The totals include 84 new species of Bivalvia and 33 of Gastropoda, 

 while one bivalve species has been re-named on account of homonymy. One new subgenus of 

 Bivalvia, Africomiodon (subgenus of Eomiodon), and one new genus of Gastropoda, Africoconnlns, 

 are erected. 



The strata which have yielded the specimens described range from Toarcian to uppermost 

 Jurassic in age. The occurrence of many species found also in the European Jurassic confirms 

 evidence from other parts of the world of the very wide geographical distribution of such forms. 

 These widespread species are particularly abundant in the Callovian and Oxfordian material. 

 At the same time, the existence of a subprovince which included countries surrounding the 

 western part of the Indian Ocean (Madagascar, Arabia, India and Pakistan, as well as East 

 Africa) is indicated by the occurrence of a number of well-characterized species found in one or 

 more of the other countries mentioned, but not in Europe. Ignoring the qualifications (" cf." 

 and " aff.") of a few identifications, these results are summarized in the following table: 









Species 





Species 





Species 



New 



known 



Species 



found in 



Geological Stage 



here 



species 



only from 



found in 



India etc. 





recorded 





E. Africa 



Europe 



but not 

 Europe 



Kimmeridgian 



92 



35 



56 



32 



3 



Oxfordian . 



53 



16 



21 



27 



5 



Callovian 



46 



5 



8 



32 



6 



Bathonian* 



10 



4 



4 



4 



2 



Bajocianf . 



44 



29 



27 



12 



4 



Toarcian 



30 



22 



22 



7 



1 



*Including Asaharbito Beds. 













tincluding Pindiro Shales. 













