LIMBS 



76 



other case both feet had six good toes. If this state 

 of aifairs had continued on down, or up, to man, we 

 should not be counting now by tens or decimals, but 

 by twelves or duodecimals — a really much more con- 

 venient system if we were only used to it ; for while 

 ten has only tw^o factors, twelve has four. 



Whether these old swimming reptiles had gained 

 these toes extra or inherited them from the lishes, 

 and whether the others have lost all but live, can 

 not be determined. If they w^ere once land-haunters 

 and went back to the water, Nature may have spread 

 the foot for them, as she has the paddle of the whale, 

 by putting in extra 

 bones. If they came 

 of ancestors which 

 were always aquatic 

 — having acquired 

 their good lungs and 

 good three - jointed 

 limbs while yet in or 

 near the water, as the 

 amphibians did, then 

 the five - toed land- 

 haunting animals 

 have lost a sixth toe. 

 It is said that there 

 is a hint of this in 

 some frogs. Against 

 this last view lies the fact that a fin or flipper does 

 not need to be three- join ted to be used as such, while 

 a good walking limb certainly does — which facts 



Fig. 38. — Foot of a chameleon, showing 

 liow the toes are bunched together, 

 and opposed to each other, in grasp- 

 ing an object. 



