On Cretaceous Cephalopoda from Zululand. 291 



elegans* seem to be a less broad periphery and less coarse, if equally 

 distant, costatiou. The proportions of diameter to thickness (3 : 2) 

 are about the same in the two forms, but on account of its broad 

 periphery d'Orbiguy's figure appears considerably more tumid than 

 that of N. manuanensis, as does the figure of the type-specimen given 

 by Foord.f On the other hand, C. pseudo-elegans is of Barremian 

 age, whereas among Albiau forms the example figured as 

 N. albensis, d'Orbigny, by Pictet & Campiche+ appears to be almost 

 indistinguishable from Crick's species. The differences are the 

 slightly greater thickness of the European species and the less pro- 

 nounced peripheral sinus in the costation, possibly also the absence 

 of bifurcation. These may not be characteis of specific importance, 

 for sexual dimorphism is proved in the recent Nautilus, and among 

 some fifteen presumably Albiau Cymatoceras from the Manuan Creek 

 there are no two alike. 



One example in the collection (No. 4991) of the following 

 dimensions- 

 Diameter . . 185 mm. 

 Thickness . . . 120 (?) 

 differs from the holotype only in showing fine costation at the end of 

 the shell, which, then, is still septate, whereas on the body-chamber of 

 Crick's figured specimen, in the one place where the test is preserved, 

 the ornament does not show this tendency to become finer and closer. 



C. virgatnm, Spengler sp., has coarser ornamentation than C. manua- 

 uense; and C. carlottense, Whiteaves sp.,|| differs in its small and 

 shallow umbilicus. 



C. crebricostatuDt, Elan ford sp.,^[ differs from .the form here described 

 chiefly in its more sinuous septa, and in a less linguiform peripheral 

 sinus of the costae. 



Locality. Middle Branch, Mauuan Creek. Coll. AV. J. Wybergh. 



16. CYMATOCERAS of. MANUANENSE, Gr. C. Crick sp. 



One example (No. 4990) agrees with Crick's holotype of N. maima- 

 nensis, but the coarse plication only appears on the shell of the ventral 



* ' Pal. Franc. Ter Cret,' (I ), 1S4O, p. 70, pis. viii and ix, fit;-. 1. The ratio of 

 diameter to thickness is 3 : 2 according to the text. 



t * Catalogue Foss. Ceph. Brit, Mus.' (II), 1891, p. 253, fig. 59 on p. 255. 



J Loc. cit. (Ste. Croix, I) (1859), p. 134, pi. xvii, figs. 1 a and b only. 



Loc. dt. (1910), p. 130, pi. xi, fig. 3. 



II "Mesozoic Fossils," I, 'Geol. Siirv. Canada,' pt. iv, 1900, p. 269, pi. xxi. 



f ' Pal. Indica,' 1, "Foss. Ceph. Cret, Rocks S. India," 1861, p. 3(3, pi. xxi, 

 fig. 3, and pi. xxii. 



