698 MR. F. G. PARSONS ON THE [June 16, 
The Extensor minimi digiti goes to the minimus and slightly to 
the annularis. 
The Lxtensor 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 metacarpt pollicis rises from the ulna as high 
as the lower margin of the lesser sigmoid cavity, also slightly from 
the radius. It has the usual insertion. 
There is no Extensor primi internodii polliis. 
The Extensor secundi internodii and Huxtensor indicts form one 
muscle, which sends tendons to the pollex, index, and medius. 
The Palmaris brevis is large. 
The Abductor and Fleaor brevis pollicis are small and united. 
There is no Opponens pollicis. 
The Abductor minimi digiti has already been described with the 
palmaris longus. 
The Fleaor brevis 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 Trunk. 
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 spine is very strongly developed, but presents 
nothing unusual. 
The Katernal 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 
llth 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 transversalis. 
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 Rectus 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 
