48 Annals of the South African Museum. 



Still greater interest attaches to a Triyonia which strongly recalls 

 the peculiar types belonging to the group of T. v-scripta in the 

 Oomia Triyonia beds and the Uitenhage group of T. vau. This 

 is T. killini Mull., found in strata ascribed to the Upper Neocomian 

 at a locality 23 km. west-south-west of Mtshinga, and it possesses 

 characters which appear to indicate relationship to one of the groups 

 mentioned rather than to the members of other groups with which 

 Dr. Miiller has also brought it into comparison. Triyonia kiihni, it 

 is true, seems to be distinguished from T. vau as well as from T. 

 v-scripta and its allies both by its less equilateral form and the 

 persistent ornaments of its escutcheon ; but to judge from the 

 description, and especially from the figure of an imperfect specimen" 

 which shows the convexity of the anterior profile and the crowded 

 ribs of the frontal series obliquely crossing the growth lines just as 

 in the Oomia T. recurva there can be little doubt about the position 

 of this shell relative to the main divisions of the genus. Whether it 

 is more closely allied to the group of T. v-scripta or to T. vau and 

 T. stowi sp. nov., cannot be ascertained until more perfect specimens 

 can be obtained and the sculpture of the youthful growth-stage 

 examined. 



Of less significance, perhaps, is the occurrence of Pecten striato- 

 punctatus Eoem., which was found w r ith Gervillia dentata, and Area 

 uitenhaycnsis Miiller, which accompanies Triyonia beyschlayi. They 

 may be brought into near comparison with Pecten pro jectus Tate and 

 Area jonesi Tate, though little importance could be attached to such 

 types as these, if taken alone. Another Pecten, from the same 

 locality as that from which P. striato-punctatus was obtained, was 

 considered by Miiller to represent very probably P. cottaldinus 

 d'Orb., which also occurs in the Uitenhage beds. The relationship 

 of the Oomia fauna to that desci'ibed from German East Africa is of 

 course what we might expect to find, having regard to the manner 

 in which a close connection between the Upper Jurassic faunas of 

 East Africa and Cutch has been demonstrated by those who have 

 studied the Cephalopoda. 



Enough has been said to indicate the position taken by these East 

 African occurrences in a widely distributed Neocomian fauna of 

 southern type, and to show that such connecting links as are 

 available, no less than the general aspect which the fauna, wherever 

 it is developed, derives from the prevalence of peculiarly charac- 

 terised Triyonice, plainly serve to unite the molluscan assemblages 

 of these three remotely separated districts in the eastern hemisphere. 



* G. Miiller (1), Taf. xxv., fig. 8. 



