_ 
THE PALATE AND ISTHMUS FAUCIUM. 949 
generally, whilst in its anterior part, where muscular fibres are wanting, they 
constitute almost its entire thickness. 
Its wpper surface, which is convex, forms a continuation backwards and 
downwards of the floor of the nasal fossee (Fig. 639), and is covered by a pro- 
longation of the nasal mucous mem- OM Se 
c re phitrum 
brane—ciliated in its upper half or eo 
more. The wnder surface is arched, ys es 
and prolongs backwards the roof of the fo ‘ 
_ Raphe of palate 
mouth, towards the cavity of which it 
looks. In front the soft palate is Uvula 
attached to the posterior edge of the Posterior 
hard palate. Zaterally it blends with palgcine aren 
the side wall of the pharynx along a Parad 
very oblique line as it slopes. downwards “Tonsil 
and backwards (Fig. 639). Its posterior acy 
margin is thin and free: it presents in 
the middle line an elongated conical 
projection, the uvula (Fig. 638), and at 
each side of this a sharp concave edge 
which, arching out, passes downwards 
and = slightly backwards into the 
posterior palatine arch (posterior pillar 
of fauces). From the under surface of 
the soft palate, 7 or 8 mm. further for- 
wards, and near the base of the uvula, 
spring another pair of ridges, the 
anterior palatine arches (anter 10r pillars Fic. 638.—OpPEN Moutd SHOWING PALATE AND TONSILS. 
of fauces), which pass downwards and _ It also shows the two palatine arches, and the pharyngeal 
Tongue 
slightly forward to the sides of the isthmus through which the naso-pharynx above com- 
19 municates with the oral portion of the pharynx 
tongue (Fig. 638). Sayre: 
T he anterior part of the soft palate 
for 8 or LO mm. (3 inch) contains practically no muscular fibres; it is composed of the 
palatine aponeurosis, covered by an extremely thick layer of glands on the under surface 
and by mucous membrane on both surfaces. This anterior portion is much less movable 
than the rest of the soft palate, and forms a relatively horizontal continuation back- 
wards of the hard palate, stretching across between the two internal pterygoid plates. It 
is upon this portion chiefly that the tensor palati acts. The posterior and larger part 
contains muscular fibres in abundance, slopes strongly downwards, and is freely movable, 
being the portion upon which the remaining palatine muscles act. 
The palatine aponeurosis, which is confined to the anterior part of the soft palate, is in 
the form of a thin flat sheet, constituting, as it were, a kind of common tendon for the 
palatine muscles which are attached to (or blended with) its posterior margin ; whilst 
its anterior margin is united to the posterior edge of the palate bone. With the 
exception of the aponeurosis of the tensor palati which passes into its lateral part, the 
muscles do not, as a rule, reach further forwards than to within 8 or 10 mm. of the 
posterior edge of the hard palate. 
The uvula, already referred to, is a conical projection, very variable in length, which 
is continued downwards and backwards from the middle of the soft palate. It is 
composed chiefly of a mass of racemose glands and connective tissue covered by mucous 
membrane, and containing a slender prolongation of the azygos uvulze muscle in its 
upper part. 
The mucous membrane of the palate, which is covered by stratified squamous epitheliun, is 
firmer and more closely adherent in front, near the rug, than behind, near the soft palate. 
Mucous glands, the orifices of which can be seen as ‘dots with the naked eye, are extremely 
abundant in the soft palate, and in the posterior half of the hard palate, except near the raphe. 
They are wanting in the anterior part of the palate, where the mucous membrane is particularly 
dense. 
The palatine ruge ( (which correspond to more strongly developed ridges in carnivora, ete.) are 
very well marked in the child at birth, although, perhaps, relatively less distinct in the foetus of 
five or six months; in old age they become more or less obliterated and irregular. At birth, 
also, and in the fcetus, the incisive pad at the anterior end of the raphe is continued over the 
edge of the gum into the frenulum of the upper lip. 
Bs 
