REPORT ON THE SPHENISCID.^. 67 



which pass between the spines of the moveable caudal vertebrae. These muscles 

 co-operate with the levator caudse in raising the coccygeal vertebrge. 



3. Depressor coccygis. 



Ahaisseurs du coccyx (one of), Vieq d'Azyr, 1774, p. 496, No. 4. 



Der Niederzieher des Schwames, Merrem. 



Der innere Niederzieher des Steissheins, Wiedemann, p. 82. 



Der Niederzieher des Steisshems, Tiedemann, p. 293, No. 2. 



Muscle No. 1, Meckel, toL vi. p. 15. 



Depressor caudce, Owen, p. 30. 



Depressor coccygis, Selenka, vol. vi. p. 101, No. 24. 



Coceygien inferieur, Gervais and Alix, p. 16. 



Attachments. — The depressor coccygis arises from the lower surface of the body of the 

 last sacral, from the lower surfaces of the bodies of aU the coccygeal vertebrae except the 

 last, and from the lower surfaces of the transverse processes of all these vertebrae. 

 The muscular fibres pass horizontally backwards, to end on a tendon which is inserted 

 close to that of the opposite side into the lower surface of the base of the ploughshare 

 bone. 



Action. — It depresses the tail. 



Relations. — The muscle lies along the under surface of the coccyx, and is almost in 

 contact with the corresponding muscle of the opposite side. 



Nerve supply. — Several branches from the anterior divisions of the coccygeal nerves. 



4. Tschio-pubo-coccygeus. 



Moteurs lateraux du coccyx (one of), Vicq d'Azyr, 1774, p. 496, No. 2. 



Der obere grosse ansdeJmcmde Schioanznmskel ()) Merrem. 



Der innere Seitenniederzieher des Steisshei7is (t) "Wiedemann, p. 82. 



Der dritte Seitenmitskel des Schwames (?) Tiedemann, p. 295, No. 5. 



Ahductetir de Ja queue, Meckel, vol. vi. p. 14, No. 2. 



Adductor caudce inferior, Owen, p. 30. 



Adductor caudce superior et inferior, Selenka, vol. vi. p. 131, No. 22. 



L'ischio-pidno-eoccygien, Gervais and Alix, p. 16. 



Attachments. — This is a broad flat muscular band, which arises from the whole 

 breadth of the posterior border of the ischium, as well as from the free cartilaginous 

 extremity of the pubic bone. The fibres pass obliquely backwards and inwards, and 

 are inserted into the transverse processes of the coccygeal vertebrae, from the second 

 to the last inclusive. 



Action. — This muscle abducts the tail from the middle line. If both muscles contract 

 simultaneously they depress the tail. 



