92 Annals of the South African Museum. 



1879. Trigonia ventricosa W. T. Blanford, in Medlicott and Blan- 



ford, Manual of the Geology of India, pt. 1, p. 261, with 

 text-figure. 



1880. Trigonia ventricosa O. Feistmantel, Foss. Flora of the Gond- 



wana System, vol. ii., p. xxxvii. (Palaeontologia Indica.) 



1893. Trigonia ventricosa W. T. Blanford, in Medlicott and Blan- 

 ford, Manual of the Geology of India (2nd edition 

 revised and partly rewritten by E. D. Oldham), p. 225, 

 with figure. 



1900. Trigonia ventricosa G. Miiller, Verstein. des Jura und der 

 Kreide. Deutsch-Ost-Afrika, Band vii., p. 543, Taf. xix., 

 figs. 4, 5. 



1903. Trigonia ventricosa F. L. Kitchin, Jurassic Fauna of Cutch, 

 vol. iii., pt. 2, The Lamellibranchiata ; p. 104, pi. x., 

 figs. 4-8. (Palaeontologia Indica, Ser. IX.). 



1905. Trigonia ventricosa A. W. Eogers, An Introduction to the 

 Geology of Cape Colony, p. 291, fig. 25 (2). 



Occurrence. This widely distributed and very characteristic form 

 occurs in the Marine Beds at various localities on the Sunday's 

 and Zwartkop's Rivers. It was collected by Messrs. Eogers and 

 Schwarz at a kloof on the left side of the Zwartkop's River, east- 

 north-east of Red House (308), and was found to occur abundantly 

 in a cliff at " Picnic Bush " ; it is also cited from localities in the 

 neighbourhood of Uitenhage, on the road to the top of Grass Ridge 

 and in the railway cutting between milestones 24J 24f on the 

 Graaff-Eeinet railway, about three miles from Uitenhage.* Mr. 

 Eogers collected it on the left side of Coega Valley, half a mile down 

 from the railway (463g), and in a small kloof three miles up the left 

 bank of Sunday's Eiver (14h, 15h). Stow remarked upon the great 

 abundance of this shell in the cliff at " M'Loughlin's Bluff" or 

 "Prince Alfred's Eest " on the Sunday's Eiver. f Krauss found it 

 in the left bank of Zwartkop's Eiver below Uitenhage, associated 

 with Trigonia herzogi and T. conocardiiformis. 



In German East Africa, shells referred to this species have been 

 found in strata ascribed by G. Miiller to the Lower Neocomian and 

 brought by him into relationship with the Uitenhage beds, at a 

 locality a short distance to the north of the Nkundi stream, 29 km. 

 north-west of Kiswere. There they occur with Trigonia beyschlagi, 

 which shows strong resemblance to T. crassa Kitchin, from the 

 Oomia marine beds in Cutch. 



* Kogers and Schwarz (1), pp. 8-10. f Stow (1), p. 502. 



