520 Reviews — Geology of Braenuw, BaUater, etc. 



Cacojps and Dissorophus, ' the Batrachian Armadillo,' break one of the 

 diagnostic characters of their class by having a sacrum of two 

 vertebrae. The rhinenceplialic chamber of the former type is no 

 doubt formed by a sphenethmoid, a bone which is shown without the 

 least possibility of doubt in Myriodon. 



The Cotylosauria, the most primitive of reptiles, are represented by 

 a very, large number of families and genera, all unique and many 

 remarkably specialized. Seymottria is perhaps the most interesting 

 of them ; it has a skull which cannot be excluded bj- any definition 

 which can be framed to include all types of temnospondj-hms amphibia, 

 united to a body which in the loss of the cleithra and posterior 

 coracoidal elements of the pectoral girdle is specialized, but which 

 has only a single sacral vertebra ! Four other types are represented 

 by complete skeletons which show a A'ery wide range of structure 

 and adaptation, together with the preservation in some of tliem of 

 primitive features, such as the wide ribs in the pectoral region which 

 are so common in the large Stegocephalia. 



Williston gives an admirably complete account of the structure 

 of Cased, a new type represented by several skeletons found closely 

 associated with Vara7iosaurus and Cacops in a bone bed unparalleled 

 in the Permian of any other part of the world. Unfortunately tlie 

 sutures in the skull are not visible, and its systematic position is still 

 quite uncertain. Varanosaurus, represented by several skeletons in 

 the same deposit, is of great interest. In its build and to some extent 

 in its structure it is very reminiscent of the lizards. The group to 

 which it belongs, the Poliosauridse, is very well represented in the 

 Texas fauna, and is regarded by Case, and, if I understand him 

 rightly, by Williston as including primitive members of the 

 Pelycosauria, the long-spined reptiles belonging, as Broom has shown, 

 to the Therapsida, the group which includes the mammal-like reptiles 

 so well known in South Africa. It is undeniable that they do show 

 many resemblances to this order, but their differences in many 

 important features are so great that it seems improbable that they 

 can really be at all intimately connected with them. , Examination 

 of the only known skull of the European Proto7'osaurus and of the 

 skeleton of that type shows no characters which are inconsistent with 

 a close relationship between it and Varmosaurus, and a very similar 

 little reptile occurs in the South African Permian. The further 

 exploitation of this fauna and the completion of our knowledge of 

 little-known types is the most interesting problem before the 

 American fossil Herpetologists, and is now being continued by 

 Professors AVillisto.n and Case with very great and deserved success. 



II — The Geology or the Districts of Bkaemae, Ballater, and 



Glen Clova. By George Barrow, F.G.S., E. H. Cunningham 



Craig, B.A., E.G.S. ; with contributions by L. W. Hinxman, 



B.A., E.R.S.E. 8vo; pp. vi, 138, with 7 plates. Edinburgh, 



1912. Price 2s. Qd. 



rPHIS memoir is descriptive of the Scottish one-inch Geological 



X Survey map, Sheet 65. A glance at the map, which is clearly 



and brightly colour-printed, shows that the area is made up almost 



