616 Mr. W. H. Workman on the Functions of the 
sinewy, and fills the entire hollow which one sees there ; it 
then descends a little obliquely in order to attach itself by a 
fleshy mass to the lateral internal face of the serpiform 
apophysis, and occupies the fossa to be observed under the 
articular face of the lower mandible. This muscle is, more- 
over, attached along the posterior edge of the styloid apophysis, 
which is close to the articular face that I have just men- 
tioned. It is separated from the foregoing by the ligament 
of which I have already spoken, which is placed between 
them both, to give them their attachment. 
“* All these muscles, on being contracted together, strongly 
elevate the posterior extremities and even the two articular 
surfaces of the lower mandible, which, being joined loosely 
with the lower edge of each quadrate, raise this bone and 
push it at the same time outwards and forwards, whilst its 
superior posterior angle rolls on itself in a different direction 
in the articular cavity of the skull where it is received. 
“You will still more readily conceive how the two quad- 
rates may be drawn forward, if you recollect that the anterior 
fibres of the Triangular Muscle are bent to form a cavity 
destined to lodge the posterior inferior angle of this bone, 
which has the effect that, when these muscles come to con- 
tract, their anterior or bent fibres tend to straighten them- 
selves, and in consequence force in front the two quadrates, 
the articulation of which with the base of the skull permits 
them to move very easily. 
“The fourth muscle which co-operates to lift the upper 
mandible is placed in each orbital fossa on the partition ; 
it is attached by a little fleshy belly under the optic foramen 
and descends, gathering up its fibres to be inserted in the 
anterior superior angle of the quadrate and the adjacent 
parts. 
“When this muscle acts, it draws upwards, inwards, and 
a little backwards the angle of the quadrate to which it is 
attached, and consequently forces the two inferior angles to 
advance, which has the effect that the slender or external 
branch which goes to the upper mandible, being joined by 
planiform or orbicular diarthrosis with the quadrate, finds 
