376 Contributions to the 



is indicated by the modification as to position of the Glu- 

 tcBi and long flexors of the leg, but by a difference in size 

 of the extensor muscles of the foot. 



Tibialis anticus. This muscle is thicker than in man, 

 and continues fleshy lower down. In the Quadrumana 

 generally, the division at the insertion, of the tendon 

 into two parts is continued up so as to make two muscles 

 more or less distinct. In the Gorilla of Duvernoy this divi- 

 sion existed only a little above the ankle, but in this Chim- 

 panzee the two parts were distinct above the middle of the 

 leg, and the posterior or internal portion which is attached 

 to the internal cuneiform bone was three times as large as 

 the other. In Vrolik's specimen this portion arose upon the 

 fibula. The anterior portion which goes to the metatarsal 

 bone is called by Prof. Wyman " Tibialis anticus minor,''^ 

 and by Meckel " Abductor longus proprius pollicis pedis" 

 The division evidently accords with the use of the great 

 toe as a thumb. 



Peroneus longus and Peroneus brevis. These are not so 

 distinct as in man. The former would act as a flexor of 

 the great toe, which enjoys considerable motion at the 

 tarso-metatarsal articulation ; there was a sesamoid bone 

 in its tendon as in man. From the external border of the 

 tendon of the P. brevis near its insertion a slender but 

 strong fascia ran along the border of the metatarsal bone, 

 and was connected above the knuckle with what seemed 

 to be a remnant of the extensor fascia of the little toe. 



Extensor longus digitorum. Origin and insertion as in 

 man. In Tyson's Chimpanzee there was no tendon to 

 the little toe, and in Owen's Orang none to the second 

 toe. I find that at the time of my dissection I made no 

 note of the ligament described by Vrolik, through which 

 run the tendons of the Extensor lons-us din-itorum. and 

 now I have no recollection of it, though I presume it was 

 present ; and Mr. Moore says the muscle on the right side 



