THE MUSCLES OF THE LOWER EXTREMITY. 217 



deflected to tlie inner side, and just above the tubercle 

 on the torso-metatarsus for the insertion of the tendon 

 of the tibialis anticus, it passes through a special little 

 bony arch there found for it. It then passes down the 

 interno-anterior edge of this bone to the trochlese of 

 the basal toe-joints. Here it divides into three smaller 

 tendinous slips ; these pass respectively over the 

 superior aspects of the second, third, and fourth toes, 

 bifurcating as they do so, beyond the basal joints, to 

 be inserted at the bases of the distal ones. At the 

 proximal extremity of each series of phalanges, the 

 tendons are bound down in the median grooves in- 

 tended for their passage and guidance by a strong, 

 fibrinous, fascia-like sheath. 



This muscle receives on its outer side a separate slip 

 that might almost be reckoned as a minor head were it 

 not in such a rudimentary state. 



It arises as a small bundle of carneous fibres from 

 a limited elliptical area on the front of the shaft of 

 the tibia, near its middle, and about opposite the prox- 

 imal end of the fibular ridge. It passes down to the 

 outer side of the extensor longus digitorum proper, and 

 in close contact with it, and about two centimetres down, 

 it develops a feeble, fascia-like tendon, which with the 

 terminal fibres of the muscle itself soon merge with those 

 of the large extensor at its side. The tibialis anticus must 

 be removed before this delicate little slip can be brought 

 into view, as it lies immediately beneath it (Fig. 51). 



Upon another occasion, when speaking of this muscle 

 as it is found in Geococcyx, I said : 



"The extensor longus digitorum (Fig. 64 bis) arises from 

 the anterior aspect of the inner half of the tibial shaft 

 as high up as the tibialis anticus muscle, which covers it ; 

 it also arises from a tense fascia which comes off from 

 the lower free edge of the procnemial crest of the tibia ; 



