ADVISORY COMMITTEE ON PAI^EONTOLOGY 1 63 



planes for the correlation of geological formations and events of 

 other continents than those in which the standards are established. 



The imperfection of the standards now in use arises from the fact 

 that they were originally defined and established in pre-evolution 

 times, before the reality of the gradual and continuous modification 

 of the life of the globe was appreciated, and only the rocks between 

 indefinite boundaries are defined by lists of their characteristic spe- 

 cies, whereas it is now seen to be essential to determine the precise 

 stage of evolution of the races whose representatives lived before 

 as well as after any artificial time boundary which may be adopted 

 as a standard. 



The sections which must be used in establishing such time bench- 

 marks are chiefly in Europe, and because they are within easy reach 

 for personal examination, European geologists may not appreciate 

 as do foreigners the necessity for their precise and full definition. 



American geologists have been driven to appreciate the importance 

 of these standard time bench-marks for the discussion and classifi- 

 cation of geological problems, and to realize that accuracy in all dis- 

 criminations of geological time values in America and throughout 

 the world depends upon the establishment of a single set of standards 

 with which to make accurate correlations of secondary standards in 

 other continents. 



The task of establishing such standards will involve comparative 

 and international investigation, and it is therefore outside the legiti- 

 mate field of the government Geological Survey of any particular 

 country. It will involve also an amount of travel and work in coun- 

 tries foreign to the investigator's home which places it beyond the 

 capacity of private enterprise of such paleontologists as would alone 

 be competent to do the work. 



It is probable that cooperation with foreign geologists, and perhaps 

 with official state surveys, may be required in executing the task, 

 and it is suggested that the Congres Geologique hiternationale is a 

 convenient agency through which such cooperation may be attained. 



Considerable investigation, correspondence, and possibly travel 

 will be required before it can be definitely estimated what shall be 

 the extent of the investigation and the amount of expense necessary 

 to complete it. 



It is therefore recommended that for the first year the Carnegie 

 Institution provide the means for a small committee of experts, au- 

 thorizing them to prepare a plan for carrying out the investigation 

 herein described, but leaving the decision as to the amount of ap- 



