COMPARING BONES. 



69 



(called in birds the tibio-tarsus), which runs from knee to 

 ankle, and the tarso-metatarsus (usually called the "tarsus"), 

 which is the part of the leg between the heel and the toe joints, 

 the part we see in life and call the " leg " of the bird. You 

 will not find anything in your own body resembling this, 

 though it really takes the place of the bones in your own foot 

 and intep, and is made up by the welding together of several 

 little bones. All you need to remember is that the name is 

 tarsus and the plural of it is tarsi. The name is important 

 because it means just that part of the leg between the heel and 



FIG. 12. BONES OF WING OF BIRD AND ARM OF MAN. 



(By courtesy of McClure's Magazine. Copyrighted, 1897, by the S. 8. McClure Co.) 



the toes, the exposed, scaly portion that we commonly see in 

 the live bird. It is frequently highly colored, so that books 

 often speak of " tarsi red," or of " yellow tarsi." 



We will not delay to study the chicken's foot, except to 

 notice that it has only four toes, but will take up the wing, 

 with its shoulder, elbow, and wrist joints clearly equivalent 

 to our own, an upper arm-bone and two fore-arm bones very 

 similar though differently modelled at the joints, and two long 

 hand-bones unlike our five in being solidly fastened together 

 at the* end. There are three fingers in place of our five, 

 though little nestling birds show traces of the other two fingers 



