Geology and Mineralogy. 355 



convenient form. The printing and appearance of the book is 

 good and the volume is well worth the money asked for it ($1.50 

 net). 



There are 14 essays, describing the historical geology of North 

 America, by Van Ilise, Adams, Walcott, Grabau, Weller, Girty, 

 David White, Williston, Stanton, Knowlton, Dall, Arnold, 

 Osborn and Salisbury. Willis presents 15 paleogeographic maps 

 with short descriptions of each one. The last essay of the book 

 is by Cbamberlin on "Diastrophisni as the Ultimate Basis of Cor- 

 relation," and Macdougal has one on " Origination of Self-generat- 

 ing Matter and the Influence of Aridity upon its Evolutionary 

 Development." 



Of new matter there is on page 37 a short note by Walcott in 

 regard to the range of Holmia in the Cordilleran region ; on 

 page 85 an eighteen-line note by Grabau in regard to the charac- 

 ter of the St. Peter sandstone in reply to Calvin's doubts as to 

 the aeolian origin of this formation ; and on page 125 a three- 

 line note by Girty. Chapter LS by Osborn did not appear in the 

 Journal of Geology and is entitled " Correlation of the Cenozoic 

 through its Mammalian Life." c. s. 



5. Paleontology and the Recapitulation Theory ; by E. R. 

 CtjMiNGS. Proc. Indiana Acad. Science, Meeting of 1909, pages 

 36. — Professor Cumings here answers the critique of the reca- 

 pitulation theory or biogenetic law by Montgomery in his " An 

 Analysis of Racial Descent." His conclusions are as follows : — 



" Paleontologists almost universally accept the theory of 

 recapitulation. Its chief critics have been embryologists. The 

 reason for the difference in attitude is probably to be sought in 

 the fact that the former ordinarily compare epembryonic stages 

 with adult characters of geologically older species, while the 

 latter too often compare embryonic stages with the adult stages 

 of existing species. It is also to be noted that in recapitulation 

 we have to do with morphological and not with physiological 

 characters, and that the row of cells from the egg to the adult 

 rnay be morphologically the same in two organisms while being 

 at the same time physiologically different. Until it can be 

 shown that two. organisms morphologically different in the adult 

 must of necessity be morphologically different at all stages, the 

 argument of Montgomery .^ Hurst and others proves nothing. 



"In the Cephalopoda, Pelecypoda, Gastropoda, Brachiopoda, 

 Trilobita, Bryozoa, Graptolites, Echinoderms and Corals, exam- 

 ples are pointed out in which there is clear and unmistakable evi- 

 dence of recapitulation. In most of these cases it is the epem- 

 bryonic and not the embryonic stages that are the basis of 

 comparison." 



The paper also cites the more important literature treating of 

 recapitulation. c. s. 



6. Ordoviciun Stromatoporoids, paper No. 7 ; by W. A. 

 Parks. Univ. of Toronto Studies, Geological Series, 1910, pp. 

 52, pis. 21-25. — Here are described 19 forms of American Ordo- 



