L. F. SjJath — Jiirassic Animonites from East Africa. 319 



fragment are flattened, but gradually rounded ofi to the periphery, 

 and very abruptly to the umbilicus ; the greatest thickness of the 

 whorl is at the umbilical edge. The small inclusion shown by the 

 impression of the inner whorl indicates a fairly large umbilicus. 



The suture-line is characterized by the slightly subdivided 

 terminal folioles of the external saddle, and by an irregularly trifid. 

 first lateral saddle. The lateral elements are highly complicated, 

 and both the saddles and their folioles are very slender. 



Observations. — The slightly falcoid constrictions and complex 

 suture-line characterize the Sjoecimen as belonging to the group 

 of Phylloceras Capitanei (Catullo) Neumayr. There is great 

 resemblance to the forms figured by Popovici-Hatzeg as Ph. 

 disputabile Zittel, especially his smaller sjiecimens ; and the 

 section given by that author (fig. 3 on p. 13) agrees very well at a 

 similar diameter. On the other hand, the suture-line of the Eg,st 

 African specimen is more comjolex and of the type of that of Ph. 

 Puschi Oppel,^ which according to Till - is often confused with 

 Ph. disputabile. In d'Orbigny's specimen and in the examples 

 referred to Ph. Puschi by Till, however, the umbilicus is only 

 6-7 per cent of the diameter. Petitclerc ^ united Ph. Puschi with 

 Ph. Lajouxense de Loriol,^ and the young of the latter species would 

 agree with the specimen under consideration in the large umbilicus ; 

 but the suture-line is too simple in Ph. Lajouxense, the whorl 

 section too inflated, and the constrictions (apparently) too straight. 



The specimen of Ph. disputahile figured by Dacque '" from the 

 Dogger of Pendambili (railway line from Dar-es-Salaam to Morogoro) 

 differs from the present example both in suture-line and in its deep 

 constrictions. According to Haug,^ however, the deep constrictions 

 and prominent bulges which characterize the typical figure of 

 Kudernatsch's appear only on the larger whorls. The umbilicus 

 also seems to close with age, for in a sjDecimen of 210 mm. diameter, 

 quoted by Pompeckj,'' it amounts to only 5 per cent of the 

 diameter. 



There is a resemblance to the forms figured by Vacek '^ as 

 Phylloceras ■ultramontanum Zittel, but in that group the constrictions 

 are more angular on the lateral area, and the elements of the 

 suture-line are very simple and plump. This latter character 

 also distinguishes the specimen under consideration from Ph. 

 mediterraneum JSTeumayr, which occurs in the macrocephalus beds of 



1 = Ph. latricum (Pusch) in d'Orbicny, Ter. Jiirass., pi. ISO (Oppel, Pal. Mitt., 

 186.3, p. 216). 



- Loc. cit., 1910, p. 259. 



■'' La ^F mine clu Callovien des Deux-Seures, 1915, p. 89. 



* " Etudes sur les Moll, et Brach. de I'Oxf. Inf. d. Jura Ledonien " : Mpm. 

 Soe. Pal. Suisse., vol. xxvii, 1900, p. 11. pi. i, figs. 1, 2,; pi. ii, fig. 1. 



5 Loc. cit., 1910, pi. V, fi.gs. 3a. 36. 



s Loc. cit.. 1891, pp. 70, 73. 



■^ Loc. cit.. Revision, 1893, p. 32. 



8 Loc. cit., 1SS6, pi, V, figs. 15-20. 



