VI I.J 



THE COMMON FROG. 



107 



addition to very numerous other muscles on both 

 surfaces, every one of the toes is provided with a 

 separate opponens muscle, each having a muscle 

 which passes from the bones of the ankle to its 

 middle foot bone or metatarsal. 



The question naturally occurs on beholding this 

 prodigality of muscles — What special purpose is 

 served by the Frog's foot t Surely mere jumping and 

 swimming cannot require so elaborate an apparatus. 



Fig. 68. — Deep muscles of exor surface of Frog's hind foot. (The numbers indicate 

 the digits to which the muscles belong.— No. i indicating the first digit or great 

 toe.) ab, abductors ; ad, adductor ; fb, flexor brevis \fp flexores profundi ; fph, 

 flexores phalangium : op, opponens muscles ; tm, transverse muscles. 



In fact, however, the Frog does make use of his 

 feet for a purpose requiring actions no less dexterous 

 and delicate than nest-building. 



