312 L. F. Spath — Jurassic Aiwinonites from East Africa. 



hand, Mr. R. B. Newton compared one of the molluscs to a species 

 from the Bathonian of Abyssinia. 



It was, therefore, of interest to obtain, if possible, more exact 

 information from a study of the Ammonites, however few and 

 fragmentary these were, and the writer is of opinion that the evidence 

 points to a probable Bathonian ^ age of the Ammonite fauna. 



DESCRIPTION OF AMMONITES 



Genus Phylloceras, Suess. 



Phylloceras aff. KudernatscJii Hauer, sp. (PI. V, Figs, la-c.) 



1852. A. heterovhyllus (Sowerby), var., Kudernatsch, "Amm. Swinitza " : 



Abh. k.k. R. A. Vienna, vol. i, pt. ii, p. 6, pi. i, figs... 5-9. 

 1854. A. Kudernatschi Hauer, " Beitr. Kenntn. Heterophyll. Ost. Mon. " : 



Sitz.-Ber. Akad. Wiss., vol. xii, pt. iv, p. 902. 

 1860. A. Kudernatschi (Hauer), Ooster, Cat. Ceph. Foss., ]}t. iv, p. 72, 



l^l. xvii, figs. 9-11. 

 1871. Phylloceras Kudenialschi{HsiueT), Neuraayr, Jurastud. (3), "Phyllocer. 



Dogger & Malm " : Jb. k.k. R.A., vol. xxi, 



Hft. iii, p. 310, pi. xii, figs. 4-5. 

 1877. ,, , (Hauer), Gemmellaro, " Sopra alcuni Fossili 



della zona con Posidonomya alpina, Gras. di 



Sicilia " : Faune Giur. & Lias., p. 128, 



pi. xviii, figs. 3 4. 

 1890. ,, ,, (Hauer), Jiissen, "Beitr. Kentn. Klans- 



Schicht. N. Alp " : Jb. k.k. R.A., vol. xl, 



p. 387, pi. ii, fig. 1. 

 1892. ,, ,, (Hauer), Neumaj'r & Uhlig, ." Ub. v. Abich i. 



Kaukasusgesaram. Jura-Fossil." : Denkschr. 



Akad. Wiss. M. Naturw. CI., vol. lix, p. 33. 

 1897. ,, ,, (Hauer), Hochstetter, " Die Klippe v. St. Veit 



b. Wien " : Jb. k.k. R.A., voL xlvii, pt. i, 



p. 141. 

 1905. „ ,, (Hauer), Popovici-Hat7eg, " Les Ceph. Jurass. 



Mt. Strunga " : Mem. Soc. Geol. France, 



vol. xiii, fasc. 3, p. 10, pi. i, figs. 1-4. 



Dimensions. — Diameter . . .39 mm. 



Height of the last 



whorl '. . . 60per cent of the diameter. 



Thickness . . . 38 ,, ,, ,, 



Umbilicus . . . 5 ,, ,, ,, 



Description. — This ammonite is a typical Phylloceras, with almost 

 closed umbilicus and an elliptical section with evenly rounded sides. 

 The specimen is not perfect, however, the shell not being continued 

 into the mass of limonite shown in Fig. la. Also, since the specimen 

 is septate throughout, it only represents the inner whorls of a larger 

 ammonite. The test is somewhat imperfectly preserved, and shows 

 fine, radial striation at the anterior portion, but near the end of the 

 shell the ornament is greatly v»'orn. Even here, however, the fine 



^ The zone of Macrocephalites inacrorephalus (Cornbrash) should be included 

 in •the Bathonian, and the Callovian considered to begin with the zone of 

 Proplanvlites Koenigi. This is contrary to Continental usage : but the 

 (English) type successions should be adhered to. 



