698 ■ MB. F. G. PABSONs ON THE [June 16, 



The Extensor minimi digiii goes to the minimus and slightly to 

 the anmilaris. 



The Extensor carpi ulnaris has the usual human attachments. 



The Supinator brevis consists of only one layer, which is super- 

 ficial to the posterior interosseous nerve ; its tendon forms the 

 external lateral ligament of the elbow, and has an orbicular liga- 

 ment attached to it. It is inserted into the upper quarter of the 

 radius. 



The Extensor ossis metacarpi pollids rises from the ulna as high 

 as the lower margin of the lesser sigmoid cavity, also slightly froQi 

 the radius. It has the usual insertion. 



There is no Extensor primi internodii pollicis. 



The Extensor seeundi internodii and Extensor indicis form one 

 muscle, which sends tendons to the pollex, index, and mediua. 



The Palmaris hrevis is large. 



The Abductor and Flexor hrevis pollicis are small and united. 



'I'here is no Opponens pollicis. 



The Abductor minimi digiti has already been described with the 

 palmaris longus. 



The Flexor hrevis and Opponens of the little finger are present, 

 and rise from the pisiform bone and the sesamoid cartilage over it. 

 ' The Intrinsic muscles of the hand are arranged in three layers, 

 as described by Cunningham and Young. The superficial and 

 deep layers correspond to Young's description of Petrogale, but 

 the intermediate layer has more muscles in it. 



Muscles of the Trunh. 



The Serratus posticus is only represented by the anterior portion, 

 corresponding to the serratus posticus superior of human anatomy ; 

 it is well developed, and is inserted into the anterior ribs from 

 the third to the ninth. 



The Erector spince is very strongly developed, but presents 

 nothing unusual. 



The External oblique rises from the third to the thirteenth ribs ; 

 the marsupial bones are developed in it, while the external abdo- 

 minal ring lies on the outer side of the middle of the marsupial 

 bones. There are three tendinous intersections — one between the 

 11th and 12th ribs, one between the 12th and 13th, and one 

 below the 13th. 



The Internal oblique is inserted into the last three ribs ; dorsal 

 to the lateral line of the body it is fleshy, while ventrally it 

 becomes aponeurotic and blends with the transversaJis. 



The Transversalis rises from the lower six ribs as well as the 

 lumbar fascia and iliac crest. In the anterior two-thirds of the 

 abdomen it passes deep to the rectus ; in the posterior third it 

 splits to enclose that muscle. 



The Eectus abdominis rises from the body, crest, and pectineal 

 line of the pubes behind the marsupial bone. It is inserted into 

 the first rib by a very short, flat tendon, as well as by its inner 



