294 ANNALS NEW YORK ACADEMY OF SCIENCES 



show that the fore feet, drawn backward by the great pectoral triceps 

 and powerful back muscles, contribute more than their share to the 

 general result. 



DIAGNOSTIC VS. CONVERGENT EVOLUTION VALUE OF LIMB RATIOS 



From inspection of the table (Plate XXXIV), it will be seen that, 

 allowing for imperfection of the fossil material and incompleteness of the 

 series, the limb ratios have a certain degree of diagnostic value when 

 taken in groups and that pure convergent evolution rarely brings about 

 a close agreement in all four ratios at once. 



The best cases of convergent evolution noted are as follows : 



Mts. Ill 

 F. 



/n . i f Perissodactyla . . . Neohipparion 1 .01 



^ursonai. . . | Artiodacty i a Odocoileus 1.00 



Travioortal I Edentata Lestodon .12 



^ ' \ Amblypoda Coryphodon 14 



f Titanotheriidse. . . Brontops robustus . . .26 



Mediportal. -j Amynodontidse. .Metamynodon 24 



^ Rninocerotidse. . . Teleoceras 2t> 



[ Toxodontia Toxodon 17 



The greatest extremes are found in the following: 



Traviportal. Amblypoda TJintatherium 10 



Cursorial. . . Giraffidse Giraffa 1.35 



T. 



F. 



Mtc. Ill 

 H 



R 

 H 



1.17 

 1.16 



1.16 

 1.05 



1.30 

 1.12 



.51 

 .61 



.17 

 .19 



.60 

 .66 



.55 

 .58 

 .57 

 .56 



.37 

 .39 

 .37 



.38 



.82 

 .81 



.78 



.77 



.53 



.19 



.70 



1.18 



1.42 



1.60 



