2°0 
while the other tendon bends and pronates; 
this, which is a direct though partial continua- 
tion of the biceps, is inserted into the ordinary 
tubercle of the radius ; whereas the other ten- 
don is attached to the fore part of the proximal 
end of the ulna. 
The muscles which arise from the internal 
condyle of the humerus are the pronator teres, 
which has the usual origin, insertion, and rela- 
tive proportions, and next the palmaris longus. 
There are, likewise, distinct and strong fas- 
ciculi of muscles corresponding to the flexor 
carpi ulnaris and radialis, and to the flexor 
sublimis digitorum. 
The strong ridge continued from the olecra- 
non to the posterior and inner part of the ulna 
gives origin to a great proportion of the oblique 
fibres of the flexor profundus; but both this 
and the flexor sublimis terminate in a single 
thick and strong tendon, which after passing 
the wrist divides into those corresponding with 
the perforating and perforated tendons here con- 
centrated upon the three long middle fingers. 
The pronator guadratus runs the whole length 
of the interosseous space, passing from the radius 
a little obliquely downwards to the ulna. 
The supinator longus, arising as usual from 
the upper part of the strongly developed ridge 
above the outer condyle, sends its tendon across 
the carpal joint, which tendon divides before it 
crosses, and is inserted by one of its divisions 
into the base of one of the metacarpal bones 
of the index finger, and the other to the adjoin- 
ing metacarpal bone. 
These are the principal muscles of the fore 
extremity which require notice in this place. 
Their modifications, in respect of number and 
Strength, relate to the act of digging up the 
soil, which is habitual in the Bandicoots, as it 
is for the purpose of obtaining food, and not for 
shelter. It is for this purpose that the three 
middle digits of the hand are developed at the 
expense of the other two, which are rudimental ; 
and we have seen that the whole powerof the deep 
and superficial flexors is concentrated upon the 
fossorial and well-armed fingers; and that by 
the single common tendon in which the fleshy 
fibres of these muscles terminate, they move 
them collectively and simultaneously. Thus 
variety of application, and especially the pre- 
hensile faculty, are sacrificed to the acquisition of 
force for the essential action. In no Marsupial 
is the hand so cramped as in the Perameles, 
sir a in the Charopus, where the functional 
and rial fingers are reduced from three to 
two. It is in relation to this condition, doubt- 
less, that the clavicles are wanting in these 
nera, while all other Marsupials possess them. 
e inverted position of the pouch in the Pera- 
meles might also be conceived to have relation 
to their imperfect hands, the mouth of the 
ney being thus brought nearer to the vulva ; 
but I am disposed to regard it as being more 
essentially connected with the habitually in- 
clined or procumbent position of the trunk in 
the Saltatorial Entomophaga. 
’ The muscles of the hinder, extremity are 
chiefly remarkable in the Kangaroo for their 
prodigious strength and unusual number: the 
MARSUPIALIA. 
“a muscle of very great strength; it termi 
accessory muscle of the biceps, e. g. is di 
into two strong fasciculi, which unite to 
inserted into the side of the lia ;* the 
riformis is also a double muscle.t 
The sartorius has its insertion so modified 
that it becomes an extensor instead of a flexor 
of the tibia: it is chiefly fixed to the tibial side 
of the patella, and by fascia into the capsular 
ligament of the knee-joint and the anter 
proximal tuberosity of the tibia. InaD 
( Das. macrurus) 1 found that the sartoriv 
had a similar disposition and office. In th 
ambulatory carnivorous Marsupial the external 
and middle glutei are so disposed as to extend 
the thigh, while the internal gluteus ini 
and rotates it inwards. 
In a Bandicoot ( Perameles lagotis ) the 
torius ran nearly parallel with and derr 
the rec/us, and was inserted into the upp 
of the patella. Besides this sesamoid, 
is rarely developed in other Marsupials, 
found a thick cartilage attached to its 
part and interposed between the common 
don of the recti and vasti, removing that te 
further from the centre of motion and ine n 
the power of the extensor muscles of the leg.” 
he rectus femoris has its two origins very 
distinct, and its analogy to the biceps of 
upper extremity is very close. f 
is a very thick and strong muscle. 
The biceps flexor cruris in the Peram 
7 
. oe 
in a strong and broad aponeurosis, which 
tends over the whole anterior part of the tik 
being attached to the rotular tuberosity of that 
bone, and terminating below in the sheath of — 
the tendo Achillis, whereby this muscle be- 
comes an extensor of the foot. 4 
It is a curious fact that all the eq nipeda 
Marsupials, whether burrowers as the Wom-— 
bat, climbers as the Koala, Phalangers, and 
Opossums, or simply gressorial, as the De 
syuride, have the tibia and fibula so connectet 
together as to allow of a certain degree of ro- 
tation upon each other, analogous to the pr 
natory and supinatory movements of the b 
of the antibrachium, and the muscles of — 
leg present corresponding modifications. 
not without interest in the question of 
affinities of the Marsupials to find that ‘ 
of the analogous carnivorous, pedimanous, 
rodent Placentals present this condition of 
hind leg. 
In the Dasyurus macrurus, the plantar 
instead of rising from the femur, has its fix 
point in the fibula, from the head to half-w 
down the bone, fleshy; its tendon passes of 
liquely inwards and glides behind the im 
malleolus to its insertion in the tar 
so that it rotates the tibia in beside 
tending the foot. The soleus has an extensive 
origin from the proximal to near the distal end — 
of the fibula. There are as usual three deep- — 
seated muscles at the back of the leg. Of 
these three the muscle analogous to the tibialis 
posticus is readily recognized; its tendon glides 
ae 
4 
* Cuvier, loc. cit. p. SOL. 
+ Ibid. p. 502. 
