EDITORIALS. 89 



ping its geological formations will furnish for the Congress at least 

 a general geological map, if not also special or analytical maps. 



Second. Such subjects as bear upon continental growth and 

 intercontinental relations. It is proposed to make this a leading 

 line of discussion during the Congress, in the belief that there is 

 no subject more appropriate, and that there is none which better 

 represents the present efforts of geologists or commands a more 

 general interest. It is hoped that analytical maps will be pre- 

 pared by the geologists of the several countries representing the 

 stages of growth of these regions in each of the great eras from 

 the Archean to the Pleistocene, and that such analytical maps 

 may constitute a leading feature of the several presentations. 

 Among the subjects upon which contributions are specially in- 

 vited are the following : The correlation of continental and 

 intercontinental orographic movements and geographic accre- 

 tions by sedimentation ; The coordination of periods of vulcan- 

 ism in the different countries ; The coordination of climatic 

 states and changes ; The correlation of faunal and floral varia- 

 tions and migrations. It is hoped that one session may be 

 devoted to such coordination papers bearing upon each of the 

 great subdivisions : viz., Archean, Paleozoic, Mesozoic, Cenozoic, 

 and Pleistocene. 



Third. Papers on Paleontological and Archeological Geol- 

 ogy of international scope. 



Fourth. Contributions to Physical, Structural and Petro- 

 logical Geology having international or general bearings. 



Fifth. Contributions to Economic Geology having general 

 bearings. 



Sixth. Miscellaneous papers of especial and general interest. 



The foregoing groups are intended to embrace and coordi- 

 nate the list of special themes announced in the circular issued 

 by the local committee some months since, except such as may 

 be best suited to popular presentation, for which special provision 

 is to be made. 



It will be determined later, when the number and nature of 

 the papers are ascertained, whether all will be arranged so as to 



