FROM TANGANYIKA AND KENYA 31 



Material. Two internal moulds (nos. L. 83863, L. 83869) preserved in pink lime- 

 stone with numerous other bivalve remains. 



Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian 

 [? or Callovian], Asaharbito Beds. 



Remarks. Largely owing to differences in the state of preservation of material 

 from different formations, specific discrimination among the Bajocian, Bathonian 

 and Callovian forms of the group of Grammatodon concinnus (Phillips), itself a species 

 of Oxfordian age, presents some difficulty. Zieten's Cucullaea sublaevigata was the 

 first species of this group to be founded on specimens from one of these stages (Bajo- 

 cian), and, since his figure agrees quite well with the specimens now recorded, parti- 

 cularly the more elongate one, his specific name is here applied to them. Later 

 names which seem to be synonymous with it include Cucullaea inflata Roemer (1836 : 

 105, pi. 6, fig. 22), Area cucullata Goldfuss 1837, Area subconcinna d'Orbigny 1850 

 (= Area concinna Goldfuss, 1837, pi. 123, figs. 6a, b, non Phillips sp.), Grammatodon 

 goldfussi Arkell 1930 (based on the same figures of Goldfuss), and possibly G. bathoni- 

 cus Cox & Arkell 1948 (= Cucullaea concinna Morris & Lycett 1853, pi. 5, fig. 7, non 

 Phillips sp.). 



Subgenus INDOGRAMMATODON Cox 1937 



Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby) 



PL 2, figs. 4, 5 



18406. Cucullaea virgata J. de C. Sowerby, pi. 22, figs. 1, 2 and explanation. 



1900. Cucullaea lasti Midler : 533, pi. 17, figs. 1, 2. 



1940. Grammatodon (Indogrammatodon) virgatus (J. de C. Sow.) ; Cox : 47, pi, 2, figs. 22-30. 



Material. Several specimens, ex B.P. Coll., those presented to the Museum 

 bearing the numbers LL. 35089-90. 



Localities and horizons. |- mile N.W. of bridge over Mkulumuzi river, 2 miles 

 W. of Tanga, Tanganyika ; Callovian. Lonji creek, W. of Mandawa, Tanganyika ; 

 Callovian(P). Along Lihimaliao stream at a point about f mile E. of Njenja, Tangan- 

 yika ; Upper Oxfordian (?). 



Remarks. These specimens agree, on the one hand, with " Cucullaea " lasti, 

 originally described from Callovian beds at a locality west of the Mahokondo creek, 

 N.W. of Kiswere, Tanganyika, and, on the other hand, with specimens of " Cucul- 

 laea " virgata from its type-area, Cutch. The number of ribs on the left valve, 

 omitting a few weak ones, some intercalated between the main ones, others occupying 

 the posterior area, varies from about 17-24 ; the number on the right valve is con- 

 siderably larger and at the same time even more variable. 



Grammatodon (Indogrammatodon) stockleyi Cox 



PL 2, fig. 9 



1937a. G. (I.) stockleyi Cox : 197, 200, pi. 16, fig. 1. 

 i960. G. (I.) stockleyi Cox ; Joubert, pi. 6, figs. 8a, b. 



