268 Revieivn — Prof. v. Koenen — North German Ammonites. 



I^ IE "V I IB 'VT s. 

 I. — North German Neocomian Ammonites. Die Ammonitiden des 



NORDDEUTSOHEN NeOCOM(VaLANGINIEN, HaUTERIVIEN, BaRRMiEN, 



UND Aptien). By Professor Dr. a. v. Koenen. pp. 451, 55 plates, 

 and 2 text illustrations. Abhaudluugen der Koniglich Preussischen 

 Geologischeu Landesanstalt und Bergakademie, Neue Folge, 

 Heft 24, 1902. 



>ROF. DR. A. V. KOENEN is so well acquainted with the 

 Neocomian deposits of Northern Germany that we heartily 

 welcome the present work, which forms the first part of a monograph 

 of the fauna of those beds. This portion is devoted entirely to 

 a consideration of the Ammonoids ; the Nautiloids, Dibranchs, 

 Gastropoda, and Pelecypoda being reserved for the second part. 

 The bibliography of the subject, most carefully prepared by the 

 author, occupies some eight and a half pages, and gives one some 

 idea of the amount of literature relating to these deposits. About 

 15 pages are devoted to the stratigraphy of the Neocomian beds 

 of North Germany, whilst the description of their Ammonoid fauna 

 occupies some 360 pages. 



In the North German Neocomian beds, that is, in the beds 

 belonging to the Valanginien, Hauterivien, Barremien, and Aptien, 

 that occur between the Berriasien (=: Wealden) and the Albien 

 (r=Gault), the author recognises the following fifteen distinct zones : — 

 Albien = Gault. 



/"Upper. Zone oi Jloplites furcaius, Sow. 

 I r i» Hoplites JDeshayesi, Leym. 



, Acatithoceras Albrechti Austriee, Hohn., and 



Soplites Weissi, Neum. & Uhlig. 

 , Ancyloceras trispinosum, v. Koen. , and Desmoceras 



Soyeri, v. Koen. 

 , Ancyloceras innexum, v. Koen., and Crioceras 



pingue, v. Koen. 

 , Crioceras Andrece, v. Koen., G. Denckmanni, 

 G. Miill., and Ancyloceras costellatum, v. Koen. 

 , Crioceras elegans, v. Koen. 

 , Crioceras Jissicostatmn, Eoem., and Ancyloceras 



crassum, v. Koen. 

 , Olcostephamcs Fhillipsi, Eoem., and Crioceras 



Strombecki, v. Koen. 

 , Crioceras capricornis, Eoem. 

 , Hoplites noricus, Eoem., and IT. radiatus, Brug. 

 , Crioceras curvicosta, v. Koen., and Olc. terscissus, 



V. Koen. 

 , Olc. psilostonms, Neum. & Uhlig, and Saynooeras 



verrucosum, D'Orb. 

 , Olc. Keyserlinffi,'Nemn. & Uhlig, and Olc. Brancoi, 



jSTeum. & Uhlig. 

 , Oxynoticeras Gevrili^W Oxh.jWilA O.heteropleurum, 

 Neum. & Uhliff. 



Aptien. 



BAKR:feMIEN. 



Hauterivien 



1 Lower. 



Upper. 



Lower. - 



{Upper. - 

 Lower. 



Valanginien.- 



Upper. 



Lower. - 



Berriasien = "Wealden. 



More than two hundred species are described, and nearly all of 

 them figured in an admirable manner in the fifty-five plates accom- 

 panying the work. The species are grouped in about twenty genera, 



