DEGLUTITION. 
formed by the Hi and ses Seca oe tter mufcle, 
together with the ftylohyoideus and pofterior portion of the 
digaftricus, carries the whole ton gue ges fo that it 
forces the portion of food into the pharynx, and oppofes 
The p h the tongue 
Pp o great in the act of drinking: th 
power of ae on ee ae the paflage of the fluid, which 
runs alon channel formed 3 in the dorfum of the tongue 5 
that apa is however, carried backwards in a certain de- 
ree, to convey the liquor a6 the aia: The fur 
progr s of the a in the pharynx, ar the aélion which 
undergoes in tha vity, cannot be underftood until the 
parts have beet: deferibe d. 
‘Vhe pharyax is a large membranous SS oe at 
i back of the nofe, an and larynx, and communricat- 
freely with thofe organs. hues nee as a aon 
cs the paflage of tbe ations for ic air to ard fro m the Ie, 23% 
in {trata flightly diftinguithed from each other, and defonbe d 
under the name of conftri€tores pharyngis mufcles. is 
bag, which is of an elongated form, extends trom the bafis 
of the fkull above to the = at which the larynx term‘- 
nates in the trachea below. ‘It is bounded at the fkull by 
the bafilar procefs of the occiput, below by the cefophagus, 
Pane isa cy lindrical peel Aad peaues from it to the 
mach ; in front by the cavities of the nofe, mouth, an 
lary behind by ie en eae. Its breadth at 
the wpper part is equal to the fpace lef. between the a 
phar ynx, when the bag is open. 
falls in breadth below, fo as to become fomewhat funnel- 
fhaped: and its moft contracted portion forms the beginning 
ba the ey ie It cannot be regal rded as a complete 
vity, fince eficient on the anter art. When its 
?P 
back furface is “Vaid open by a per aici cut, we fee no- 
thivg in front but the openings of the nafal and laryngeal 
cavities pi mouth, The pharynx is therefore an imperfect 
bag, common in the greateft part o yas extent to the air and 
food ; ond nterpo ofed between the external openings, whic 
give admiffion to thofe, and ther cineca and digeftive or- 
occiput, and the body of the fphenoid, by a ftrong and 
— is peas fubftance, firs is gradu nae loft on the 
mbra It is ued below into the cefo- 
phagi Sopeae he firlt aalsiens rings oF he trachea ; 
and a fudden contraction at this part, ener externally, in- 
dicates the point of continuity betwee eh ri belly 
The lateral ey are the parts giv ae origin to the co 
ftritor mufcles; viz. the pterygoid Roeeliee, cornua of 
the os hyoies, "and the fides of the seer and cricoid 
al a: es 
aking an internal view of its lateral connections, we 
and mouth, towards the upper part 5 a below the bag 
poffefles _ anterior portion, which is clofely conne€ted to 
f the tongue, and which lies. againit the back of 
‘The external furface of the bag is conneéted to the bodies 
Vo I, 
L. 
of the vertebre behind by’ a loofe cellular fubftance: and 
along its fides we notice the courfe of the carotid arteries 
and lee vein 
The fides of ine a are compofed of mufcular fibres 
Aiea, and of membrane on the infide. The latter is a 
ae of the gene cial mucous membrane, which be- 
longs to the digeftive and refpiratory organs, ‘I'his is e3 
panded in an uniform manner over the pofterior furface of 
the bag, and by its anterior prolongations on either fide be- 
linirg of the Enu®tachian tube rer down it is ed 
with the pharyngo- ee ali arches, and through ean with 
the lining as es out thé ne itill it paffes over the front 
of the lar ojeétion which ie ae of that 
orgaa ae into the nds ot pe pharynx. qpening 
of the Cia it eee continuous with the ene thac 
lines che organ of the voice the of the pharynx it _ 
is extended ‘along te under furface of the body of the {phe- 
noid bone, and thus becomes continuous with the aay) 
membrane at the Gone margin of the cheane nari 
a bettom it ts prolonged by a circular continuation into 
ceefophagus. It is {mouth on its furface, and. pofleffcs 
confide rable vafcularity : it contains many mucous aes 
affording a ss wh:ch moiitens the part, and facilitates 
the food through its cavity. 
e are four in number, ac- 
nt rns; but much more 
eleriptions of fome nies eee Tt fol- 
lows nee ia ly, from the preceding defeription that they 
- she fituated at the back of the pha 
fede 
rynx oon to the bafis of the fkull. 
cover three broad, thim, and flattened mufcles, named con- 
Jfriiores phargnsit, expanded like an uniform mufcular coat 
at the back an ag; diftin@ from each sree 
ir imately united on the pharynx, 
e fibres from 
“ a fides of the body. 
Conftridor Phargrsie. ea (thyreo-pharyngeus and crico- 
pharyngeus).— arifes from the fide of the ericoid carti- 
lage, from the inferior cornu, and bac the ala of wi 
ae ; Its fibres yt poe a to expan 
wer part o ) The fuperior potion 
pion: obliquely pase the midale of the bag, where, to- 
gether with thofe of the oppotite fide, they cae ina 
inted form ; the middle fibres are tran{verfe, and the in- 
s figure approaches on the 
whole to the lozenge. Iti is in come - its pofterior fur- 
face, with the mufcles on the front of the vertebre ; and en- 
tirely with ee pad salary tylo-pharyogeus, Lsaaee 
pharyngeu ane o oid elend rynx. IJti ered 
a little at fie “fide a the thyr 
Conflrifor pharyngis media (iyo-phar ae: — This 
mufcle is exactly of the lozenge figure. Its origi is from 
mufcle; the middle o ones euiine a tranf{verfe courfe, and the 
fuperior afcend to terminate a a iad extremity fixed above 
inte 
