DISCRIMINATION OF TIME-VALUES IN GEOLOGY S79 



and biochron to the units whose measure is the endurance of 

 organic characters, we have a means of constructing a system of 

 nomenclature which will express what is now known of geological 

 time relations, and (more important still), which will serve as an 

 aid in accumulating the necessary statistics to perfect the geo- 

 logical time-scale. 



ORDER OF MAGNITUDE OF BIONIC UNITS. 



In expanding this system of nomenclature the following 

 table will indicate the principle upon which the fundamental 

 units of time value will be discriminated and named. The time 

 unit of lowest rank will be based upon the life endurance of an 

 individual organism ; the amount of organic vigor expressed by 

 the preservation of the individual life constitutes a bionic unit of 

 simplest or lowest rank ; the individual, therefore, is an organic 

 unit of monobionic rank. How many individual lives are possi- 

 ble in the life-history of a species we at present do not know, 

 but we do know that the bionic value of the species (or, strictly 

 speaking, of specific characters) is of an entirely higher order 

 than that of the individual. To be more concrete the individual, 

 the species, the genus, etc., constitute organic units of consecu- 

 tively higher and higher order of bionic magnitude, which state- 

 ment may be tabulated in the following way: 



THE BIONIC VALUES OF THE SEVERAL CATEGORIES OF CLASSIFI- 

 CATION OF ORGANISMS. 



Individual - - a monobionic unit. 



Species - - a diobionic unit. 



Genus - - a tribionic unit. 



Family - - a tetrabionic unit, 



Order - - a pentabionic unit. 



Class - - a sexbionic unit. 



In the table the bionic order of magnitude is expressed by 

 the prefix mo7io-, di-, tri-, etc.; thus the dibiohic unit is an abstract 

 mode of naming the order of magnitude of the organic force 

 expressed in preserving, by generation, the specific characters of 

 an organism. Comparing this with the force which preserves in 

 like manner generic characters, the former is seen to be of second 



