1897.J NEW YORK ACADEMY OF SCIENCES. 361 



Epitrochleo-anconeus into the olecranon succeeding those of the 

 medial head of the Triceps. 



Summary. 

 The main facts, heretofore not described, concerning the 

 muscle groups with which the paper deals, are as follows : 



1. Presence of an axillary arch from Latissimus dorsi to the 

 Pectoral insertion, replacing the cutaneous muscular slips de- 

 scribed by Murie and Mivart in L. catta and hj Lucse in L. 

 macaco. 



2. Arrangement of the Pectoral insertion : 



a. Connection as just stated with a slip from Latissimus dorsi, 

 reproducing the condition found as a distinct variet}' of the 

 human axillary arch. 



b. Connection of the abdominal division of the Ectopectoral 

 with the Entopectoral at the insertion into the lateral humeral 

 ridge. 



c. Folding of the Sterno-costal sheet of the Ectopectoral at 

 the insertion. 



d. Insertion of clavicular portion of Ectopectoral into the 

 superficial aspect of tendon of the sternal division, and fusion 

 with adjacent margin of Deltoid. 



e. Lateral recession of caudal portion of Ectopectoral and 

 Entopectoral origin. 



3. Coracobrachialis presents a division into upper, middle 

 and lower portions, the latter inserted into the root of the 

 supracondylar arch. The musculo-cutaneous nerve perforates 

 the middle division. 



4. Presence of a large and distinct Epitrochleo-anconeus 

 muscle, passing from the supracondylar process and medial 

 condyle to the medial margin of the Olecranon. 



5. Union of Brachialis anticus and lateral humeral head of 

 the Triceps, both extending nearly to the proximal end of hu- 

 merus on the lateral aspect of the shaft. 



6. Among the trunk muscles the arrangement of the Supra- 

 costal muscle is to be especiall}^ noted, extending from the car- 

 tilage of the 1st rib to the 3d, 4th and 5th cartilages and the 

 border of the mesosternum. 



7. In the abdominal group the structure of the External 

 Oblique aponeurosis clearl}^ foreshadows the condition found in 

 higher Primates, especiall}^ in relation to the construction of the 

 External abdominal ring, Gimbernat's ligament and the Trian- 

 gular or Colles' ligament of Human Anatomy. 



The examination of the above detailed muscular groups in 

 Lemur leads to certain general considerations in reference to 

 the affinities of the genus. 



