Reviews — Geology of Illinois. 425 



(London) , both of which are of considerable size and well executed ; 

 the latter contains besides a carefully arranged column of formations, 

 a column of lithological remarks, and very numerous well chosen and 

 well engraved figures of characteristic fossils. Messrs. Lowry and 

 Etheridge's later Chart of the Tertiary fossils (Stanford, London), is 

 a further and excellent adaptation of the same plan to a separate 

 stratigraphical system. 



By making the Organic Eemains the chief objects of a geological 

 table, and setting one class, or order, in its manifold developments, 

 to indicate the successive stages of deposits, several very useful 

 charts may be constructed besides the one of Crustacea by Salter and 

 Woodward, already published by J. Lowry (London, 1865), and 

 well known to geologists. 



The gradual working-out of British geology in the field, by the 

 Geological Survey of the United Kingdom, has necessarily been a 

 most important element in the growth of true stratigraphy, proving 

 and knitting together all that is good in the observations and deduc- 

 tions of the earlier geologists and of contemporaries, and bringing 

 out in maps and memoirs the perfected lists of strata and fossils of 

 district after district. A generalized catalogue of the British forma- 

 tions is therefore to be found in the Explanatory Table of the Colours 

 of the Greological Survey Maps of England, Scotland, and Ireland, 

 as well as in the Tabular View of the Aqueous and Fossiliferous 

 Eocks of Britain in the preface (p. Ixxviii) of the "Catalogue of the 

 Collection of Fossils in the Museum of Practical Geology," 1865, 

 whilst the fossils of the groups are enumerated (but not in a con- 

 secutive order) in this '•' Catalogue." 



Of course, foreign Geological Surveys aid in the collation of the 

 strata of different countries ; but this is a very extensive subject, 

 and belongs to special memoirs rather than to general tables. 



If by the foregoing remarks we have aided the student in finding 

 such geological tables as he requires, and have indicated how the 

 existing tables may be improved and multiplied, our aim is reached. 



T. E. J. 



m. — Geological Survey of Illinois, A. H. Worthen, Director. 

 Vol. I. Geology. 4to. 1866, pp. 504, with eleven maps and 



engravings. Assistants : Professor J. D. Whitney, Professor 



Leo Lesquereux, and Mr. Henrv Englemann. 

 Vol. IL PalfBontology. 4to. 1866, pp. 470, with 50 plates. Verte- 



brata : MM. J. S. Newberry and A. H. Worthen. — Invertebrata: 



MM. F. B. Meek and A. H. Worthen.— Plants : M. Leo 



Lesquereux. 

 Vol. III. Geology and PaljBontology. 4to. 1866, pp. 574, with 



20 plates.— Geology : MM. A. H. Worthen, H. Englemann, H. 



C. Freeman, and H. M. Bannister. — Palaeontology by MM. F. 



B, Meek and A. H. Worthen. — Published by authority of the 



Legislature of Illinois. — London : Triibner & Co. 



FOLLOWING the example of the State of New York, the Legisla- 

 ture of Illinois, in 1851, passed an Act autliorizing a Geological 



