THE LONG ROAD 



cene times they were nearly all flat. The arched 

 foot, too, comes in; this is an advance on the flat 

 foot. The bones of the palms and soles are not locked 

 until the later Tertiary. The vertebral column pro- 

 gressed in the same way, from flat to the double 

 curve and the interlocking process, thus securing 

 greatest strength with greatest mobility. In the 

 earliest life locomotion was diffused, later it be- 

 came concentrated. The worm walks with its 

 whole body. 



IV 



If we figure to ourselves the geologic history of the 

 earth under the symbol of a year of three hundred 

 and sixty-five days, each day a million years, which 

 is probably not far out of the way, then man, the 

 biped, the Homo sapiens^ in relation to this immense 

 past, is of to-day, or of this very morning; while the 

 origin of the first vertebrates, the fishes, from which 

 he has arisen, falls nearer the middle of the great 

 year. Or, dividing this geologic year into four di- 

 visions or seasons, primary, secondary, tertiary, and 

 quaternary, the fishes fall in the primary, the rep- 

 tiles in the secondary, the mammals in the ter- 

 tiary, and man in the early quaternary. 



If the fluid earth hardened, and the seas were 

 formed in the first month of this year, then probably 

 the first beginning of life appeared in the second 

 month, the invertebrate in the third or fourth, — 

 March or April, — the vertebrates in May or June, 



21 



