a new Classification of Ammonites. 373 



here the descriptions of tlie newly established genera, I confine 

 myself to citing the works in which they have been described, 

 and giving a few examples of them. In the works indicated, 

 there will be found especially the descriptions of the septa 

 characteristic of each genus. The names of the authors 

 followed by the dates of their publications refer to the biblio- 

 graphic note at the commencement of this article. 



PnTLLocERAs, Suess, 1865, 6. Zittel, 1868, 56 ; 1870, 153. Neu- 

 mayr, Jahrb. geol. Reichsanst. 1871, xxi. 297. Heterophylli, von 

 Buch, Ueber Ammoniten, 1832. Triassic, Jurassic, and Cretaceous. 

 Examples : Ph. Jarhas, heterophijUum, tatricum, Ziynodianum, 

 ptychoicum, Thetys. 



Lytoceras, Suess, 1865, 8. Zittel, 1869, 70 ; 1870,162. Fimbriati, 

 lineati. Triassic, Jurassic, and Cretaceous. Examples: L. Shnonyi, 

 splicer ophyllum, fimbriatum, Eudesianum, Adelce, Liehigi, subfim- 

 briatum. 



Arcestes, Suess, 1865, 6. Globosi. Triassic. Examples : A. fjaUi- 



formis, subumbiliaitus, cymbiformis. 

 PiNACOCERAS, Mojsisovics, Verhaudl. geol. Reichsanst. 1872, 315. 



Triassic. Example : P. MetternicM. 

 Trachyceras, Laube, 1869, 15. Triassic. Example : T. Aon. 

 Artetites, Waagen, 1869, 69 ; 1870, 98. Arietcs, Von Buch ; par- 



tim capricorni. Triassic and Liassic. Examples : A. Biwhlandi, 



obtiisus. 



yEgoceras, "Waagen, 1869, 69 ; 1870, 199. Partim capricorni, coro- 



narii, ornati, macrocephali, &c. Triassic and Liassic. Examples : 



^. incidtum, planorbis, anyidatum, Henleyi. 

 Amaltheus, Montfort. Waagen, 1869, 69 ; 1870, 207. Amalthei, 



Von Buch ; partim ornati, falciferi, pulchelli, clypeiformi. Triassic, 



Jurassic, and Cretaceous. Examples : A. oxynotus, maryaritatus, 



pustulatiis, cordatus, Lamberti. 

 Harpoceras, Waagen, 1869, 245, 250 ; 1870, 202. Falciferi, Von 



Buch ; partim disci, insignes, clypeiformi. Jurassic. Examples : 



H. radians, opalinum, Jiecticum, discus. 



Oppelia, Waagen, 1869, 72 ; 1870, 203. tEkotraustes, Waagen, 

 1869, 25. OppcHa, Zittel, 1870, 175 ; partim denticulati, disci, 

 cl}T)eiformi, ligati. Jurassic and Cretaceous. Zittel has united 

 under this name the two subgenera Oppelia, Waag., and CElv- 

 trawites, Waag. ; he has separated from it the genus Haploceras. 

 Examples: 0. sidyradiata, temdlobata,Jle.vnosa. 



Haploceras, Zittel, 1870, 166. Jurassic and Cretaceous. Examples : 



H. Erato, ooUticum, Grasianum. 

 Strphanoceras, Waagen, 1869, 248 ; 1870, 205. Coron.uii, Von 

 Buch ; partim macrocephali, coronati, denlati, bullati, &e. 

 Jurassic and Cretaceous. M. Waagou at first made of iSlephano- 



