G10 DR. ROLLESTON ON THE HOMOLOGIES OF CERTAIN 



views which I now put forth, and in which I should have more confidence if I knew 

 them to be in accordance with his views. 



The pectoralis secundus s. levator humeri of ordinary birds arises from a greater or less 

 extent of the keel and lateral portions of their sternum ; and narrowing into a tendon as 

 it passes along the inner aspect of the coracoid and the inferior surface of the coraco-cla- 

 vicular membrane, from both of which structures it may receive an accession of muscular 

 fibres, it winds over a pulley formed for it by the bone just mentioned, to be inserted 

 between the insertion of the great pectoral on the radial tuberosity of the humerus, 

 internally, and the tendon of the deltoid as it passes down to its attachment on the 

 outer aspect of the bone, externally. The tendon of the levator humeri holding thus an 

 intermediate position between the tendons of the deltoid and the great pectoral, may 

 receive an accession of muscular fibres from the mesoscapular portion of the scapula ; or 

 these fibres, which may have a separate nerve-supply, may have also a separate insertion from 

 that of the levator on the humerus. But the pulley arrangement furnished by the cora- 

 coid enables the levator in its simplest form to act as a powerful levator of the humerus. 



The " subclavius " of anthropotomy arises from the cartilage of the first rib, a region 

 into the constitution or near neighbourhood of which Mr. Parker has shown the epico- 

 racoid to enter in several mammals 1 . Under cover of a dense fascia (the " costocoracoid 

 membrane," which may be taken to represent in fibrous tissue 2 an aborted larsre-celled 



Muscles of the Vertebrate Limb," Cambridge Journal of Anatomy and Physiology, May 1867. "On Muscular 



Anomalies 



iv. Xo. 5, May 1868. 



Hi 



Dr. Hair. « On the Arrangement of the Muscular Fibres of the Alligator/' Cambridge Journal of Anatomy and 

 Physiology, November 1867. 



Profes^r Pagenstceher. «Ein Vergleich der Muskulatur des Drill mit der des M.nsehen," In. Zoologische Garten, 

 Zeitschnft fur Peobachtung, Pflege und Zucht der Thiere, April and May 1867, Frankfort. 

 A\ . F. Vrolik. Den Carpus der Zoogdiercn. 1866. Leiden. 



Wood 



i»ar\ i oon ,t ,o„„s " u ' xm ' P- z:jy V nnc ie > l8 04), vol. xiv. p. 385 (June 



Cambrulge Journal of Anatomy and Physiology, November 1866 



iM',n!tI ymim ' " " th ° %mmC " 7 "' H ° m0l0W ° f LimbS '" ** tato " »*■ **• soc. v„,. x , June 1867, 



My thanks are clue to Messrs. Vrolik Minn- TTo^^f^ to i i m 

 of their pap™, several of which ,vcre ,„„ Id! I \ " ' yman ' ^ ** ""*" ''" 8en,li "" mC "*■ 



, a I her" S^ Id I T °" '""^f^^" ~»% < ' 868) p^ed ,, y , llc ,,, v B. ,,. famishes. 



afficl to L2 One of T , ' ° dCte ™ iMi ™ <* >»»"*" >«™>— which to writer c I the n.tarr 



it! r TeL , I SPaK ° M 9 "" th ° taSk ° f «"*H *» ** — '- 1, ,„™. -before Mr. Pat-her, 



Mu 



.usculus 



structures of what was cartilage in the embryo, see 



>. pp. 182, 184, 107, 198. For the existence of th. 7i T g ° "* ° '°' "* ' 



suchungen zur verdeiehenden A-JLS^E ** ^ ^ 0US ba » d > a ^* -ntioned, see (;, ,-nbaur, ■ Unter- 



who, however, does not mention Prof (WtW ' ' if ' . ' ^ * P " "* Prof * Pa 8 en8teCIlCr 



^ ^ e,lbaurs discovery, speaks, in the description of the di ction of a Drill 



