Chap. 8.] Bones of the foes. - 125 



the thumb. There are fometimes found fmall bones, 

 which are called ofTa fefamoidea j thefe chiefly occur 

 between the firft and fecond joints of the great toe and 

 thumb, and as they anfwer the fame purpofes, viz. 

 that of removing the tendon further from the axis of 

 motion, may be considered as fmall patellae. They are 

 almoft exclufively found in perfons advanced in life 

 and inured to hard labour, and therefore are by fome 

 fuppofed to owe their origin to friction. 



