FROM TANGANYIKA AND KENYA 65 



Holotype. No. LL. 35100, ex B.P. Coll. The only specimen. 



Locality and horizon. Lihimaliao creek, Mandawa area, Tanganyika ; Upper 

 Oxfordian. 



Remarks. The original convexity of the holotype, a rather crushed specimen, 

 does not appear to have been very strong. The ornament recalls that of the two 

 Liassic species Pseudolimea pectinoides (J. Sowerby) and P. roemeri (Brauns), and, 

 although its internal characters are unknown, the species is referred to Pseiidolimea 

 with some confidence. Lima mistrowitzensis Boehm (1883 : 638, pi. 69, figs. 21, 22), 

 from the Tithonian Stramberg beds, is a comparable species, but has fewer radial 

 ribs. 



Genus LIMATULA Wood 1839 



Limatula moorei sp. nov. 



PL 8, figs, ya, b 



Specific name. After Mr. W. R. Moore, of the Tanganyika Geological Survey, 

 collector of the holotype. 



Diagnosis. Small (height 9-0 mm., length 7-0 mm.), tall, ovate, slightly asym- 

 metrical, with prominent umbo ; surface evenly inflated. Ornament confined, as 

 in all Limopsis, to median part of flank, and consisting of smooth, rounded, not very 

 prominent ribs separated by intervals which are only about one-third as wide as 

 ribs and bear delicate growth-threads near ventral margin. Ribbed part of surface 

 merges gradually on both sides into smooth anterior and posterior parts ; number 

 of ribs, apart from very weak outer ones, about 15. 



Holotype. No. LL. 16799, a right valve. The only specimen. 



Locality and horizon. Usigiwa river, 6 miles W.S.W. of Kiwangwa, Baga- 

 moyo hinterland, Tanganyika ; Upper Oxfordian. 



Remarks. The broadly rounded ribs and narrow intervals distinguish this form 

 from most of the species of Limatula described previously from the Middle and Upper 

 Jurassic, including L. boehmi de Loriol, L. consobrina (d'Orbigny), L. gerassimovi 

 Pchelintsev, L. gibbosa (J. Sowerby), L. globularis Laube, L. helvetica (Oppel), L. 

 oxfordiana Maire, L. praedispersa Krause, and L. rauracica Cossmann. In L. 

 minutissima (d'Orbigny) ( = Lima minuta Roemer non Goldfuss ; synonym, Lima 

 suprajurensis Contejean) the ribs are just as broad as in the species now described, 

 but they are scaly or tuberculate, while the shell itself is more distinctly truncated 

 posteriorly. 



Limatula migeodi sp. nov. 

 PI. 8, figs. 4«, b 



Specific name. After the late F. W. H. Migeod, for some years leader of the 

 British Museum East Africa Expedition. 



Diagnosis. Small (height of holotype 10-5 mm.), ovate, breadth nearly three- 

 quarters of height ; slightly oblique. Auricles moderately large, obtuse-angled, the 



