FROM TANGANYIKA AND KENYA 103 



Protocardia bipi sp. nov. 

 PL 17, figs, i, 2, 3«, b 



Specific name. After " B.P. " (British Petroleum Co. Ltd.), whose geologists 

 collected the type material. 



Diagnosis. Of medium size (length of largest specimen c. 28 mm.), very variable 

 in shape and proportions, ovate to trigonally ovate, subequilateral to strongly in- 

 equilateral, beaks from anterior fifth of length to submedian, length exceeding height 

 to a variable extent, inflation moderately strong. Umbones rather narrowly 

 rounded, moderately prominent, well incurved to the beaks, which vary from ortho- 

 gyrous to strongly prosogyrous according to their position. Postero-dorsal margin 

 subhorizontal to gently sloping, posterior margin subvertical to strongly oblique, the 

 two meeting in an even curve ; ventral margin symmetrical and feebly convex to 

 strongly asymmetrical with posterior flattening ; anterior margin flat to feebly con- 

 vex, its inclination variable. A distinct diagonal ridge, well marked in earlier 

 growth-stages, delimits the slightly flattened posterior area. Flank unornamented 

 except for growth-rugae. Posterior area with fine radial grooves. 



Holotype and paratypes. Holotype, no. LL.35129 ; several paratypes, in- 

 cluding nos. LL. 35130-31 ; all ex B.P. Coll. 



Locality and horizon. Lihimaliao creek, at a point near Mbaru creek, Man- 

 dawa area, Tanganyika ; Bajocian (?), Pindiro Shales. 



Remarks. This species is highly variable. The more elongate specimens show 

 some approach in shape to P. besairiei, described above, but their beaks are not 

 prosogyrous, the umbonal ridge does not persist to the postero-ventral angle of the 

 shell, and the flank is more delicately ornamented. 



Protocardia consobrina (Terquem & Jourdy) 

 PL 16, fig. 5 



1869. Cavdium consobrinum Terquem & Jourdy : 102, pi. 11, figs. 1-3. 



Material. Two specimens (nos. LL. 35 132-33), ex B.P. Coll. 



Locality and horizon. Changogo-Magindu track 4 miles from Changogo town, 

 Tanganyika ; Callovian. 



Remarks. In these specimens, the larger of which is 27 mm. long, the shell is 

 suborbicular and strongly and evenly inflated, with no diagonal ridge present at any 

 stage of growth. The umbo is submedian and moderately prominent. The flank is 

 smooth, while the posterior area bears shallow radial grooves, about 12 of which are 

 distinguishable on the better preserved specimen, separating flattened radial riblets. 



I cannot distinguish between the African specimens and P. consobrina, as described 

 and figured by its authors from the Bathonian of France. A French Callovian spe- 

 cies, P. boonei Cossmann (1924 : 47, pi. 6, figs. 57, 58), is very similar in size and 

 shape, but has finer and more numerous radial riblets on its posterior area. P. 



