^"'■.y^ri Leach, The Myology of (he Dell-Magpie. 23 



outer side of the femur, about one-third of its length down the 

 shaft of that bone. 



The accessory femoro-caudal, another of Garrod's muscles, is 

 absent in the Raven and the birds under notice. He used five 

 muscles. These were : — 



The ambiens. 



The femoro-caudal (denoted by A). 



The accessory femoro-caudal (denoted by B). 



The semitendinosus (denoted by X). 



The accessory semiteudinosus (denoted by Y). 

 The first and third are absent in the birds under discussion. 

 Their muscular formula on Garrod's system is A X Y — that is, 

 the femoro-caudal, the semitendinosus, and the accessory semi- 

 tendinosus are present, as they are in the Piciformes and the 

 Passeriformes, except the Drongo {Dicruridce), which has the 

 muscle formula AX. 



104. The obturator externus [30] is a thick, fleshy muscle arising 

 from the lower posterior half of the ilium. It runs forward as a 

 fleshy mass, becomes tendinous, and is inserted on the femur below 

 the trochanter and above the insertion of the femoro-caudal (loj). 

 This muscle is bent down to provide for the passage of the sciatic 

 nerve and artery above it. 



105. The obturator internus [30] in Strepera agrees with Shufeldt's 

 description of the muscle in the Raven. It arises internally from 

 the ventral surface of the ischium. It has a central tendon, to 

 which the fibres converge. The strong tendon passes up through 

 the obturator foramen to be inserted overlying the gemellus, into 

 the outer aspect of the trochanter of the femur. 



106. The gemellus [30] is a fleshy, thick muscle between the 

 back of the femur and the pelvis. It arises on the outer side of 

 the pelvis, and passes directly with the tendon of the obturator 

 internus (105), to be inserted on the trochanter of the femur. 



107. The addvtctor longus [30], a flat, board-like muscle, arises 

 from the lateral aspect of the pelvis below the obturator externus 

 (104). It passes downward and forward to be inserted down the 

 back of the femur, from above the insertion of the femoro-caudal 

 (103) down to the internal condyle. It is closely related to the 

 next muscle, the adductor magnus (108). 



108. The adductor magnus [30] is longer and more slender in 

 Strepera than is (107). It arises below the ischiatic fossa on the 

 outer lateral edge of the pelvis. Its fibres pass to be inserted 

 into the internal condyle of the femur. The internal head of the 

 gastrocnemius is attached to this muscle above its insertion. It 

 is also bound in a fascia with the adductor longus (107). 



THE MUSCLES OF THE LEG AND FOOT. 



These are named by Shufeldt — 

 log. The gastrocnemius. 

 no. The sole us. 



