SECOND LAYER OF MUSCLES. 205 



Dissection (fig. 77). To complete the preparation of the second LayJre 

 \\ er <>f muscles, the abductor hallucis should be detached from the 

 js calcis and turned inwards. The internal plantar nerve and 

 irteiy, and the superficial portion of the external plantar nerve, 

 ire to be cut across and thrown forwards; but the external plantar 

 irti-ry and the nerve with it are not to be injured. All the fat, 

 tnd the loose tissue and fascia, are then to be taken away near the 



SECOND LAYER OF MUSCLES (fig. 77). In this layer are the Muscles of 

 tendons of the two flexor muscles at the back of the leg, viz., flexor 

 ongus digitorum and flexor longus hallucis, which cross one another. 

 Connected with the former, soon after it enters the foot, is an 

 accessory muscle ; and at its division into tendons tor the four 

 outer toes the fleshy lumbricales are added to it. 



The tendon of the FLEXOR LOXGUS DIGITORUM (fig. 77, B), enters Tendon of 

 the foot beneath the annular ligament, and there lies on the internal jj"^" ' 

 at era 1 ligament of the ankle-joint. In the foot it is directed 

 obliquely towards the centre, where it is joined by the accessorius divides into 

 muscle and a slip from the tendon of the flexor longus hallucis, and four ; 

 divides into tendons for the four outer toes. 



Each tendon enters the sheath of the toe with and beneath a these pierce 

 tendon from the flexor brevis (E). About the centre of the first tendon? 1 ; 

 !>halanx the tendon of the long flexor (F) passes through the other, 

 and goes onwards to be inserted into the base of the ungual phalanx. 

 Uniting the flexor tendons with the two nearest phalanges of the 

 toes are short synovial folds, one to each, as in the hand ; and the 

 lescription of the sheaths on p. 75 should be referred to. to 'tendons; 



Action. It flexes the last phalangeal joint, and combines with use. 

 the short flexor in bending the first and second joints. If it acted 

 by itself it would tend to bring the toes somewhat inwards, in con- 

 sequence of its oblique position in the foot. 



The LUMBRICALES (fig. 77, D) are four small muscles between Four lum- 

 the tendons of the flexor lougus digitorum. Each arises from two bncales : 

 tendons with the exception of the most internal, which is connected attachment 

 only with the inner side of the tendon to the second toe. Becoming flexor 

 tendinous, they pass upwards on the tibial side of the four outer and exten- 

 toes, and are inserted into the expansion of the extensor tendons on so 

 the dorsum of the first phalanx ; but they often end partially in an 

 attachment to the side of the first phalanx. The muscles decrease 

 in size from the inner to the outer side of the foot. 



Action. These small muscles assist in flexing the metatarso- 

 phalangeal joints ; and through their union with the long extensor 

 tendon they may aid that muscle in straightening the two inter- 

 phalangeal joints. 



The ACCESSORIUS MUSCLE (fig. 77, A) has two heads of origin : Flexor ac- 

 One is mostly tendinous, and is attached to the outer surface of the cessorms 

 os calcis, and to the long plantar ligament ; the other is large and 

 fleshy, and springs from the inner concave surface of the bone 

 (fig. 76, p. 201). The fibres end in aponeurotic bands, which join 

 the tendon of the flexor longus digitorum about the centre of the longus ; 



