FROM TANGANYIKA AND KENYA 39 



Modiolus (Inoperna) perplicatus (Etallon) 

 PI- 3. %• 14 



1862. Mytilus perplicatus Etallon, in Thurmann & Etallon : 223, pi. 29, fig. 8. 



1913. Modiola (Pharomytilus) perplicata (Etallon) ; Dietrich : 73. 



19146. Modiola perplicata (Etallon) ; Hennig : 176, pi. 14, fig. 4. 



i960. Modiolus (Inoperna) perplicatus (Etallon) ; Joubert, pi. 6, figs. 13a, b. 



Material. Six specimens. 



Localities and horizons. 3 miles N.E. of Melka Dakacha, N.E. Kenya ; 

 Upper Kimmeridgian, Dakacha Limestones. Tendaguru, Tanganyika ; Upper 

 Kimmeridgian. Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru, Tanganyika ; 

 Upper Kimmeridgian, Indogrammatodon Bed. 



Remarks. This species differs from M. (I.) sowerbianus in that each of the oblique 

 ribs meeting the dorsal margin bifurcates half-way to the diagonal carina and is thus 

 replaced by exactly two weaker ribs. In Europe this form occurs only in the 

 Kimmeridgian. 



Genus MUSCULUS Roding 1797 



Musculus kindopeensis sp. nov. 



PI. 4, figs. la, b 



Diagnosis. Small (length of holotype 9-3 mm.), moderately elongate, with the 

 length, measured parallel to the hinge-margin, rather less than twice the height, not 

 greatly oblique, ornamented, as in typical Musculus, with radial threads which are 

 absent from the concave area separating the antero-ventral lobe from the most 

 inflated part of the shell, which runs diagonally from the beak to the postero-ventral 

 corner. The threads of the posterior series number about 36 where they meet the 

 margin; those of the anterior series about 12. 



Holotype and paratypes. Holotype, no. LL.11331. Six paratypes, nos. 

 L.56234, LL. 11328-30, LL.11332, LL.11516. 



Locality and horizon. Scarp at Kindope, 2 miles N.N.W. of Tendaguru, 

 Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 



Remarks. This form is less elongate and smaller than the European Kimmerid- 

 gian-Portlandian species M. autissiodorensis (Cotteau) (de Loriol 1868 : 625, pi. 12, 

 fig. 8 ; 1875 : 152, pi. 18, fig. 14). 



Genus MYTILUS Linnaeus 1758 



Subgenus FALCIMYTILUS Cox 1937 



Mytilus (Falcimytilus) tifoensis sp. nov. 



PI. 3, figs. 12, 13 



1957. Lyceltia dalpiazi Venzo ; Saggerson & Miller : 14. 



Diagnosis. Of medium size (diagonal measurement from beak to postero- 

 ventral corner 39 mm. in the holotype), markedly falciform, oblique (the diagonal 



