92 THE VOYAGE OF H.M.S. CHALLENGER. 



its insertion into the radius, cannot be considered as homologous with the brachialis 

 anticus of other birds. Neither does it constitute the representative of the Biceps, seeing 

 that it is not inserted into the interosseous border of the radius. 



3. Flexor profundus antihrachii. 



Le flediisseur profond de Vavant bra^, Vicq d'Azyr, 1773, p. 573, Xo. 8. 



Le profond fleelmsenr, Cuvier, vol. i. p. 293. 



(V) Described by INIcrrem. 



Der kurze Ellenbogensirecker, Wiedemann, p. 91. 



Kurze Beuger des Ellenhogenheins, Tiedemann, p. 313, K'o. 6. 



Der kurze Beuger des Ellenbogenheins, Heusinger, p. 185, No. 15. 



Muscle No. 6, Meckel, vol. vL p. 50. 



Der tiefe Beuger des Voi-derarmes, Schoepss, p. 142, No. 29. 



Attachments. — Schoepss found this muscle present in Spheniscus demersus, and 

 describes it as a slender muscle which arises from the lower part of the anterior border 

 of the humerus. From this point it descends, lying parallel to the deeper fibres of the 

 brachialis internus, and after crossing the humero-radial articulation is inserted into the 

 radial border of the ulna, close to the ligamentous capsule of the elbow joint. 



Remarhs. — I failed to recognise the presence of this muscle in any species of Penguin 

 which I dissected. In this respect my observations agree with those of Meckel, who 

 asserts the absence of this muscle in the Penguin. Gervais and xVlix, moreover, omit all 

 reference to it in their description of the myology of Eudyptes chrysolophus. 



4. Anconeus. 



Attachments. — The muscle so named is said by Eeid to be present in Aptenodytes 

 loiigirostris, where it arises from the lower end of the humerus, and is inserted into the 

 sesamoid bones of the elbow. 



According to Gervais and Alix, it is represented in Eudyptes chrysolo'phus by the 

 tendon which attaches the external sesamoid bone of the elbow to the upper extremity 

 of the ulna. 



Remarks. — I failed to recognise this muscle in any species of Penguin. The 

 ligament which, according to Gervais and Alix, replaces it, is present in every S23ecies 

 of Penguin, but appears to me to be simply that portion of the tendon of insertion of 

 the triceps which attaches the external sesamoid bone to the upper end of the ulna. 



5. Pronator quadratus. 



Attachments. — Pieid describes this muscle in Aptenodytes as "arising as is usual 

 in this class." 



