FIRST LAYER OF MUSCLES. 199 



The inner septum separates the short flexor from the abductor 

 hallucis ; and the outer, from the abductor minimi digit! . 



The superficial transverse ligament crosses the roots of the toes, Transverse 

 and is contained in the skin forming the rudimentary web of the JJJJ^"* 

 foot. It is attached at the ends to the sheath of the flexor tendons 

 of the great and little toes, and is connected with the sheaths of the 

 others as it lies over them. Beneath it, the digital nerves and 

 vessels issue. 



The sheaths of the flexor tendons (fig. 77, G, p. 203) on the toes Sheaths of 

 are similar to those of the fingers, though not so distinct, and dons!^ 

 ^rve to confine the tendons against the grooved bones. The sheath 

 is weak opposite the articulations between the phalanges, but is 

 strong opposite the centre of both the metatarsal and the next 

 phalanx. Each is lubricated by a synovial membrane, and contains 

 the tendons of the long and short flexor muscles. 



Dissection (fig. 75). In the sole of the foot the muscles are Dissect first 

 numerous, and have been arranged in four layers. To prepare the muscles. 

 first layer, all the fascia must be taken away; but this dissection 

 must be made with some care, lest the digital nerves and vessels, 

 which become superficial to the central muscle towards the toes, 

 should be injured. 



The tendons of the short flexor muscle are to be followed to the 

 toes, and one or more of the sheaths in which they are contained 

 should be opened. 



FIRST LAYER OF MUSCLES. In this layer are three muscles, viz., Muscles hi 

 the flexor brevis digitortmi, the abductor hallucis, and abductor 

 minimi digiti. The short flexor of the toes lies in the centre of the 

 foot ; and each of the others is in a line with the toe on which 

 it acts. 



The ABDUCTOR HALLUCIS (fig. 75, A), the most internal muscle of Abductor 

 the superficial layer, takes origin from the inner side of the larger hallucis : 

 tubercle on the under-surface of the os calcis (fig. 76), from the ongm; 

 plantar fascia, from the lower border of the internal annular liga- 

 ment, and from the internal intermuscular septum. In front, the 

 muscle ends in a tendon, which is joined by fibres of the short 

 flexor, and is inserted into the inner side of the base of the first insertion ; 

 phalanx of the great toe. 



The cutaneous surface of the muscle is in contact with the relations ; 

 plantar fascia ; and the other touches the tendons of the tibial 

 muscles, the plantar vessels and nerves, and the tendons of the 

 long flexors of the toes, with the accessorius muscle. 



Action. This abductor acts chiefly as a flexor of the metatarso- use, as 

 phalangeal joint of the great toe, but it will slightly abduct that abductor, 

 toe from the others. 



The FLEXOR BREVIS DiGiTORUM (flexor perforatus, fig. 75, B) Flexor 

 arises posteriorly by a pointed process from the fore part of the JJJJJJ dlgl " 

 larger tubercle of the os calcis (fig. 76), from the overlying plantar 

 fascia for two inches and the septa. About the centre of the foot 

 the muscle divides into four slips, which become tendinous and are 

 directed forwards superficial to the tendons of the long flexor to 



