ANATOMY OF REGIONS. 
227 
their exit. The posterior border is limited behind by the transverse 
process of the atlas. 
5th. The different organs forming the layer underneath the parotid 
are irregularly arranged. First, forward and above are found blood 
vessels and nerves, which we will speak of as we go further on. Im¬ 
mediately under the ear, and backwards, on a level with the middle of 
the transverse process of the atlas, the small oblique muscle,* covered 
by the tendon of the mastoido humeralis.f The inferior border of 
the small oblique runs obliquely upwards, to be inserted upon the mas¬ 
toid process ; it projects somewhat over the stylo-hyoideus or occipito- 
hyoideus muscle. 
The direction of the fibres of the stylo hyoideus is perpendicular to 
that of the fibres of the small oblique, and it is easily felt by the finger 
running in front of the fibres of this short muscle ; as above, one feels 
the styloid process of the occipital, while downwards, and a little for¬ 
ward, at a distance of about 2-J- to 3 centimeters, upon an eminence of 
median size, is met the posterior border of the grand branch of the 
hyoid bone. It is in the space thus included between these two bones, 
in the very fibres of the occipito styloideus, that the puncture, to pene¬ 
trate into the guttural pouches, must be made, which -indeed lines the 
internal face of the muscle. 
Altogether behind the stylo hyoideus, without well defined demark- 
ation, one finds the superior part of the digastricus muscle, or stylo max- 
illaris, whose consistency is more marked than the other. This muscle 
runs soon forward and downwards, crossing obliquely the great axis of 
the region, and it reaches the anterior border of the gland, from under 
which it exits entirely at the antero-inferior angle. 
Let us mention, also, in this layer, the superior border of the max¬ 
illary gland found at the posterior part, and towards the inferior third 
of the region. This gland is situated on a level somewhat deeper than 
the superior belly of the digastricus. It is separated from the deep face 
of the parotid by a thin aponeurosis, which is continued upwards with 
the tendon of the mastoido humeralis, and downwards with that of the 
sterno maxillaris, which passes over the surface of the digastricus, be¬ 
tween it and the gland. 
6 th. The deepest organ of that region is the guttural pouch, kind 
of bladder placed upon the track of the Eustachian tubes, communicat¬ 
ing on one side with the pharynx, and on the other with the middle ear. 
The guttural pouch extends, specially in the supero-anterior part of 
* Obliquus capritis posticus minor of Percival. 
t Levator humeri of P. 
