Reviews — Dr. Mourlon — Geology of Belgium. 431 



The Jurassic beds of Luxemburg do not appear to have been tlie 

 subject of any striking observations since 1868, but the Cretaceous 

 rocks have yielded numerous results of importance. Thus in the 

 Wealden (^Aachenian) of the Bernissart Colliery we have the recent 

 discovery of several entire skeletons of Iguanodons of from nine to 

 ten metres in length, together with numerous remains of land and 

 river Chelonians. Here also are many freshwater fishes, the specific 

 determination of which is not yet completed, as well as a Wealden 

 Flora, consisting chiefly, according to Count de Saporta, of marsh 

 plants, thus contrasting with those of the same age found at La 

 Louviere, which, as the late Abbe Coemans pointed out, are more or 

 less Alpine in character. All these fossils occur in clay filling up a 

 fissure in the Coal-measures. In the Meule de Bracquegnie, a forma- 

 tion generally poor in fossils, Messrs. Cornet and Briart have 

 succeeded in collecting some 120 specimens of Gasteropods and 

 Lamellibranchs, Cephalopods and Brachiopods being remarkable 

 by their absence. To the same associated geologists, and to 

 Dr. Barrois, much of our improved knowledge of the subdivisions 

 of the Belgian Chalk is also due. As to the Tertiary rocks which 

 cover so much ground in Belgium, the mass of detailed observations 

 of recent date which Dr. Mourlon has had to incorporate is per- 

 fectly enormous. This was to be expected in the classical birth- 

 place of Tertiary Geology, and it is natural that the author should have 

 felt it his duty to devote what, to non-Belgian readers, might appear 

 almost too much space to these beds. Among the novelties in this 

 department must be reckoned the application of Yanden Broeck's 

 theory of the alteration of portions of deposits by the percolation of 

 rain-water to the clearing up of many interesting points in the history 

 of the many subdivisions recognized in these deposits. In con- 

 nexion with this subject, as in many other cases, the author has 

 had access to much unpublished material placed at his disposal by 

 the investigators themselves, thus adding greatly to the value of 

 his book as an original work. 



The first 240 pages of vol. ii. consist of full lists of fossils from 

 each formation, the rest being a complete bibliographical list of 

 papers, books and maps relating to Belgian Geology. For the 

 purposes of the paleeontologist and the foreign " researcher " the 

 usefulness of this part of the work cannot be overestimated. 



As a second edition is sure to be called for, it may not be amiss to 

 draw Dr. Mourlon's attention to some omissions which a hasty 

 perusal of the " Bibliography " has revealed. English authors have 

 suffered most, and we look in vain for the names of Dawkins, J. 

 Geikie, Jenkins, Lebour, Simpson, and several others, some of 

 whose writings bear on the geology of Belgium. The author has 

 certainly not searched through the publications either of the 

 Palseontographical Society of England or of the North of England 

 Institute of Mining Engineers. Even the Geological Magazine 

 and the Geologist are all but ignored, and the Eoyal Society's 

 Catalogue of Scientific Papers has not been put under contri- 

 bution. 



