REVIEWS 689 



The two arched reptiles are placed in three superorders. In the 

 first (Diaptosauria) are placed the Rhynchocephalia and Thecodontia. 

 (Proterosaurus finds a resting place in the latter.) This association seems 

 unfortunately conservative. Sphenodon and its allies at present appear 

 to be only remotely related to the other diapsids, while the thecodonts 

 are unquestionably ancestral to the dinosaurs, which comprise Nopcsa's 

 second diapsid superorder, and to the pterosaurs and crocodiles. The 

 last two are united in the superorder Praepubci, for no reason other 

 than the supposed presence of a prepubis in both groups. But it is quite 

 doubtful whether the Crocodiha have a prepubis; the muscular argument 

 cited by Nopcsa can be disproved. Otherwise there seem to be no 

 features common to the crocodilia and flying reptiles other than primitive 

 archosaurian characters. 



The work shows evidences of a very careful consideration of the 

 recent literature, and, no matter what opinions may be held as to some 

 of the conclusions, furnishes stimulating reading for anyone interested 

 in reptilian phylogeny. 



A. S. ROMER 



Sammlung geologischer Fiihrer. Berlin: Gebrlider Borntraeger, 



1923. Vol. XXII, Die Westtiroler Zentralalpen, by Wilhelm 



Hammer. Pp. 150, figs. 22, plate 3. Price $0.75. Vol. 



XXIII, Helgoland und die umliegenden Meeresgrunde, by 



Otto Pratje. Pp. 115, figs. 8, maps 4, profiles 2. 



Two new geological guidebooks in the extensive series being 



published by Gebriider Borntraeger. 



R. T C 



