1897.] NATURAL SCIENCES OF PHILADELPHIA. 43 



ialis anticus. Accepting this union as valid, the cephalo-humeral 

 system ends by the insertion of the Brachialis anticus upon the ulna. 



The Brachialis anticus is a large, powerful muscle ; it arises by 

 two heads, one in continuity with the Deltoideus at the pectoral 

 ridge, and the other (the larger) from the outer surface of the shaft 

 just below the origin of the outer head of the Triceps. It has a 

 broad tendinous insertion on the ulna. It is more important appar- 

 ently than the Biceps, and unlike the same muscle elsewhere in the 

 mammalia it is not associated with the Triceps. 



The Rhomboideus is small without capitate slip. An important 

 difference is here noted in Burmeister's description. The Rhomboi- 

 deus is figured with an accession about the position of Rhomboideus 

 major, and a large muscle resting on the Splenius named Levator 

 posticus scapulm which is the same as the capitate fascicle of later 

 writers. The Academy's specimen shows no muscle intervening be- 

 tween the Sterno-cleido-mastoideus and the Splenius. 



The Levator anguli scapu lot arises from the transverse processes of 

 the fifth to the seventh cervical vertebra?, and is inserted on the 

 superior angle of the scapula. 



A muscle arises from the front of the atlas in association with the 

 Longus colli, and is inserted upon the acromion in connection with 

 the Trapezius. This is the Levator anticus scapuloz of Burmeister's 

 figures, but is not described. 



The Latissimus dorsi is without axillary arches and arises entirely 

 from the dorsal aponeurosis, where the muscle is 23 mm. wide. This 

 is also the case in Burmeister's specimen. The slip to the olecranon 

 is in close union with the connective tissue over the median nerve 

 and brachial artery, and the impression is received that the slip pro- 

 tects these structures from the effects of friction and pressure. 



The other muscles not embraced in the preceding group are the 

 following : 



The Omo-hyoideus is broad, conspicuous and without intersection. 



The Biceps flexor is relatively a weak muscle. The association 

 with the Coraco-brachialis conforms to the primate type. 



The Triceps muscle is fully described by Burmeister who, how- 

 ever, includes it in the slip to the olecranon from the Latissimus 

 dorsi. The third head (Anconeus tsrtius) arises from the supra-con- 

 dyloid ridge in part. The three heads do not form a single 

 tendon of insertion. The first two heads are almost separate and 

 measurably distinct from the third. The Anconeus constitutes a 



