Vol. XIV. 

 1914 



] l^-EKCU, The Myology of the Bell-Magpie-, 3'3 



the Raven, from the post-pubic process and the neighbouring 

 parts of the pelvis. It passes forward to be inserted into the 

 posterior edge of the last rib. Its mesial border is free. 



146. The rectus abdominis [57] arises by a tendinous membrane 

 from the post-pubic element of the pelvis, and from the ligament 

 that joins the two post-pubic processes. It agrees with Shufeldt's 

 description of the muscle in the Raven. At first it is tendinous, 

 and becomes muscular at a definite line. It runs to the sternum, 

 and is attached, but is continued as a thin membrane to be 

 attached to the outer side of the ribs under the other abdominal 

 muscles which have been described. 



147. The transver sales abdominis [57] is a definite muscle, well 

 developed in Strepera, as it is in the Raven. It arises from the 

 ligament between the post pubes and the under side of the pelvis. 

 It becomes fleshy, runs forward over the peritoneum to be inserted 

 over the inner side of the ribs. VentraUy, it is inserted into the 

 linea alba. 



148. The diaphragm. — Shufeldt describes three rudimentary 

 muscles in association with the diaphragm of the Raven. Though 

 I specially dissected two specimens of each of the Raven, Gym- 

 norhina, and Strepera, I did not succeed in satisfying myself that 

 these rudimentary muscles were present. 



The remaining muscles are concerned with the movement of 

 the tail. 



149. The levator coccygis [60] and (150), the levator caudce of 

 Shufeldt, are not distinct in Strepera, the Austrahan Raven, 

 Gymnorhina, or Cracticus, though Shufeldt found them to be 

 distinct, though closely related, and connected with fascia, in 

 the American Raven. Shufeldt regards the levator coccygis as 

 the detached portion of the longissimus dorsi (130), which in 

 most reptiles is continuous to the tail. It arises from the posterior 

 aspect of the pelvis and the caudal vertebrae. It is inserted, in 

 Strepera, into the tuberosity on the anterior margin of the 

 pygostyle and also into each neural spine of the caudal vertebrae ; 

 further, it is inserted fleshy over the four inner tail quills on each 

 side. Gadow, in Bronn's " Klassen der Their-Reichs," vi., Band, 

 figures this muscle mass as " one." 



151. The transver sns perinor [62] is a flat sheet of muscle 

 arising from the lower edge of the ischium and the post-pubic 

 process. It forms a loop for the passage of the femoro- caudal 

 muscle (103), and runs down to meet its fellow of the under side 

 just before the anus. Gadow figures two muscles connected with 

 the anus — a circular band about the anus and the sphincter muscle 

 in the margin. These are present in Strepera and the other birds 

 examined. 



152. The depressor -caudcB [61] [62] arises from the posterior 

 border of the ischium and the post pubis, as Shufeldt described 

 for the Raven. The fibres converge, and are inserted into the 

 base of the three outer rectrices. 



3 



