242 Annals of the South African Museum. 



there is an immature, evolute specimen from the Umpeuyati Eiver, 

 Natal, recorded by Crick" ; on the other hand, five specimens from 

 the Umtamvuna Eiver, Natal, in the British Museum, identified by 

 Crick, represent more strongly ornamented varieties, with increasing 

 tuberculation round the umbilicus. One of these examples (No. 

 C19425) is slightly constricted and transitional to a highly tuber- 

 culate species named " Schloenbachia" papillata by Crick. 



Specimens of the latter species, also of the transitional form, from 

 Zululand and belonging to the Albany Museum, were sent to the 

 writer in 1914 through the kindness of Mr. Woods, but since 

 Crick had been at work on his paper on this fauna for many years, 

 and since there were only a few specimens, they were not described. 

 P. p(ti>ill<tta, G. C. Crick MS. sp., is not represented in the present 

 collectiou,f nor are the transitional forms, referred to above. 



The three specimens were collected at Umkwelane Hill, Umfolozi, 

 Zululand (Coll. Dr. A. L. du Toit). 



GEN. DIAZICEKAS, nov. 

 Genotype : I), tissotiaeforme, sp. nov., p. 245, PI. XIX, figs. 1 a-lf. 



This genus is created for one form in the collection that cannot be 

 included in any of the known genera of keeled Seucnian Ammonites. 

 Its suture-line stamps it as being near to the genera Eulophoceras, 

 Hyatt, and Splieniscoceras, Crick MS.,J and in general outline this 



* Lnc. cit. (1907), p. 250. 



t Two additional specimens of tliis species were included in the collection 

 from the Durban Museum, already referred to, and will be figured. 



This genus was created for the three species S. africanum, S. minor and 

 5. tenue, G. C. Crick MS., which obvioxisly are the " other species of Eulopho- 

 ceras " referred to by Woods (loc. cit., p. 337). Crick, in his diagnosis of the new 

 genus, does not in any way mention the genus Eulophoceras, which, however, is 

 very close, as will be seen on comparing the suture-lines given in Text-fig. C J 

 with that of Eulophoceras natalense, Hyatt (Text-fig. C 2, after Woods, loc. cit., 

 pi. xlii, fig. 8), and with Hyatt's type (Pseudoceratites, 1903, p. 86, pi. xi, 

 figs. 2-6). On the other hand, Crick considered the new genus to be " inter- 

 mediate between Placenticeras and Sphenodiscus," which statement is meaning- 

 less, even from a purely morphological point of view, for Spheniscoceras has a 

 thickened keel, after the style of that of the remarkable form figured as A. 

 roissyanus, d'Orbigny, varietas, by Ooster (Catalogue, etc., 1860, pi. xxvi, fig. 7), 

 or of certain Dipoloceras and Pseudophacoceras described in this paper (see, e. </. 

 PI. XXV, fig. 1 d, and PI. XXVI, fig. 56), placed on a very thin and acute whorl. 

 This is an exaggeration of the feature shown in Hyatt's fig. 6 a of pi. xi, but of 

 doubtful generic importance. Haiifriceras rembda, Forbes, shows a similar 

 feature occasionally. In fact the writer is not convinced that Crick was right in 



