September 5, 1919] 



SCIENCE 



233 



sediments, so that there is often a decided 

 lithic and faunal distinction between the 

 deposits of the several provinces. 



In the British province the chalk shows a 

 transgressive character from the southeast to- 

 wards the northwest, and generally begins 

 with a basal clastic series which rests upon the 

 eroded surface of various older formations. 

 This is followed by greensands and glauconitic 

 chalk, which formations are thus lithic rather 

 than stratigraphic units, being of Aptiau age 

 in southeast England, of Cenomanian age in 

 southern Antrim, Ireland, and of Senonian 

 age in northern Antrim. The age of the base 

 of the pure chalk varies in like manner. From 

 the detailed analysis of the sponge faunas of 

 Great Britain, it appears that there was in 

 general a corresponding shifting in the max- 

 ima in the same general direction, the sili- 

 ceous sponges of the Cenomanian. Turonian 

 and Emsherian, being confined to the southern 

 and southeastern counties, while the Senonian 

 sponge fauna is best represented in Norfolk 

 and Yorkshire. 



A similar transgressive character of the 

 Cretaceous sea and corresponding overlap and 

 change of facies of the sediments is seen in 

 the deposits which underlie the Tertiaries of 

 the Paris Basin, and which are structurally 

 stratigraphically and faunally united with 

 those of southeast England and belong to the 

 sediments of the Boreal sea of Cretaceous 

 time. Marine conditioiife in part of this 

 region began however in Lower Cretaceous 

 time. The deposits of southern France, to- 

 gether with those of the Alps, belong to the 

 persistent Tethys sea, and here extensive ma- 

 Tine limestones accumulated in Lower Creta- 

 ceous time as well. The Cretaceous deposits 

 of northern Germany (indicated upon an ex- 

 cellent copy of Walther's map, which un- 

 fortunately is reproduced on too small a 

 scale), and those of Bohemia, also illustrate 

 the transgressive character of the Cretaceous 

 sea, most extensive in the Cenomanian, and 

 further show a striking general change in 

 facies from prevailingly sandy (Quadersand- 

 stein) on the east to calcareous character on 

 the northwest, the calcareous facies beginning 



as intercalations of thin-bedded limestones 

 (Planer) in the sandstone series. Local con- 

 tributions of sands from the Harz uplands, 

 etc., also modify the facies, but the main 

 events of Cretaceous paleogeography of the 

 northern European basin as indicated by the 

 sediments were the progressive transgression 

 of the sea towards the west and north and the 

 simultaneous advance of the terrigenous sands 

 from the Bohemian and Vienna regions over 

 the calcareous deposits, the two types being in 

 the relation of replacing overlap. This is the 

 key to the distribution of the sponge fauna 

 of the several districts. 



The bibliography which is limited to Cre- 

 taceous Silicispongise and important strati- 

 graphic papers contains 280 titles all of which 

 except 24 were consulted by the author, surely 

 a remarkable piece of industry when it is con- 

 sidered that many of these are monographic 

 works, and that several European languages 

 are represented. 



A few typographical errors have crept in, 

 those noted being as follows : p. 52, end first 

 paragTaph, the reference to the following table 

 should be to the preceding tahle; p. 61, 

 Wealden anticline is used instead of Wealden 

 anticlinal as elsewhere, to indicate the com- 

 pound character of this structure. 



Altogether the work here reviewed is most 

 creditable, alike to the author and to the geo- 

 logical-paleontological department of the mu- 

 seum, and while it does not pretend to be an 

 original contribution either to spongiology or 

 to European stratigraphy, it is distinctly one 

 in its keen analysis of European literature, 

 and in the synthesis of the important facts of 

 European stratigTaphy into a comprehensive 

 and very readable unit and for this American 

 students will be grateful to the author. 



A. W. Grabau 



ORGANIZATION OF THE AMERICAN 

 SECTION OF THE PROPOSED 

 INTERNATIONAL GEO- 

 PHYSICAL UNION 



At the invitation of the Eoyal Society 

 issued Jime 17, 1918, an Inter-Allied Confer- 

 ence on International Scientific Organizations 



