Emu 



26 Leach, The Myology of the Bell-Magpie. [ ,^^*'"]^,,y 



114. The extensor halUicis brevis [38] is a small but very inter- 

 esting muscle. Strepera agrees with the American Raven as 

 described by Shufeldt for this muscle, which arises fleshy from the 

 front of the inner head of the tarso-metatarsus, and from the 

 neighbouring fascia about the tendons, especially that of the 

 tibialis anticus. The delicate fibres pass down in a shallow groove 

 along the shaft of the bone. They give rise to a strong tendon 

 which passes round the accessory metatarsal and along the outer 

 side of the basal joint of the hallux to be inserted into the base 

 of the ungual phalanx. 



115. The tibialis posticus [39] arises from the fibula below the 

 insertion of the biceps flexor cruris (99) from the adjacent parts 

 of the tibia. Some of its fibres blend with the flexor perforans 

 digitorum pedis (116), which partly overhes its anterior upper part. 

 It forms a strong tendon, which is inserted into the outer, upper 

 edge of the tarso-metatarsal bone. 



116. The flexor perforatus indicis secundus pedis [40] [43] [45] 

 is a small spindle-shaped muscle arising from the external condyle 

 of the humerus. Its fibres blend with those of the anterior border 

 of the tibialis posticus (115), and soon form a tendon which passes 

 through the tibial cartilage and the hypotarsus down the back 

 of the tarso-metatarsus and under the annular ligament of the 

 foot. It here forms a sheath for the perforating tendon, and 

 bifurcates into two slips about the middle of the second phalanx 

 of the index toe. Each shp of tendon is inserted into the lower 

 side about the middle of the second phalanx. 



117. The flexor longus hallucis [41] [46] arises tendinous by two 

 heads. The first arises from the under surface of the femur and 

 the second from the external condyle. The fibres soon unite, 

 and pass down the back of the leg, narrowing to form a strong 

 tendon. This tendon passes through the tibial cartilage and the 

 hypotarsus to the inner side of the leg, and runs down the back 

 of the tarso-metatarsus, superficial to the tendon of the flexor 

 perforans digitorum profundus (122), to the apex of the accessory 

 metatarsal bone. It winds round to the inner side of it, and runs 

 in a groove to be inserted on a tubercle on the base of the ungual 

 phalanx of the hallux. This is one of the plantar tendons made 

 so famous by Garrod. This is more fully set out after the descrip- 

 tion of muscle 122. 



118. The flexor perforatus annularis primus pedis [41] [43] has 

 a long name, but, as it is given according to Shufeldt's effective 

 system, it is self-explanatory. It is the muscle whose tendon is 

 perforated on the fourth toe (corresponding to the ring finger), 

 and is inserted into the first phalanx of that toe. This muscle in 

 Strepera arises tendinous from the under side of the humerus, 

 and runs down closely applied to the last muscle (117). The 

 fibres flatten out, and then converge to form a tendon which runs 

 through the tibial cartilage and the hypotarsus with the tendon 



