ANATOMY. 
iiteus ; 5. flexor longus digitorum pedis; 
6 to 9. lumbricales pedis ; 10. flexor lon- 
gus liallucis ; 11. tibialis posticus ; 12. pe- 
roneus longus ; 13. peroneus brevis ; 14. ti- 
bialis anticus ; 15. extensor longus digito- 
rum pedis ; 16. peroneus tertius. 
Muscles of the foot.— 1. Extensor pro- 
prius liallucis; 2. extensor brevis digito- 
rum pedis ; 3. flexor brevis digitorum pe- 
dis ; 4. abductor liallucis; 5. transversus 
pedis; 6. abductor digiti minimi pedis; 
7. flexor brevis digiti minimi pedis ; 8 to 10. 
interossei interni pedis ; 11 to 14. inter- 
ossei externi pedis. 
The muscles of the lower extremity are 
54 ; and the whole number of the body 289. 
But as they are the same on both sides, this 
must be doubled, which will give 578 ; an 
enumeration which is pretty nearly correct. 
ORGANS CONCERNED IN THE REDUCTION 
AND ASSIMILATION OF THE FOOD. 
Organs of mastication and deglutition . — 
The two jaws, with their teeth, and the 
tongue, are the principal agents in the bu- 
siness of mastication. 
The articulation of the condyle of the 
lower jaw with the glenoid cavity of the 
temporal bone, admits of the former pait 
being moved in various directions. Its de- 
pression and elevation cause the opening 
and shutting of the mouth. It can be 
brought forwards, and carried backwards ; 
and admits also of being moved to one side 
or the other. It is by a combination of 
these various motions that the food is mas- 
ticated, or reduced into a soft and pulpy 
form. The different teeth, which are placed 
in various parts of the cavity of the mouth, 
are adapted, by their form and situation, 
for various parts of the process of mastica- 
tion. The anterior ones, which have a thin 
Cutting edge, and in which the superior 
overlap the inferior, act like the blades of 
a pair of scissars. These cut the food into 
smaller morsels ; and serve us also in biting 
off a portion from any mass of food which 
we may be eating. The back teeth have 
broad bases, furnished with obtuse promi- 
nences ; and they shut perpendicularly on 
each other. These are therefore well adapt- 
ed for the grinding and trituration of the 
food. As their office requires a greater 
muscular force, they are placed in the back 
of the mouth, near to the centre of motion, 
and where, consequently, the action of the 
muscles is felt with the greatest effect. The 
cutting teeth are placed in front, at a 
greater distance from the attachment of 
the muscles, because their office does not 
require so great a muscular exertion. 
The tongue is of considerable utility in 
contributing to mastication, as it serves to 
move the food about in the cavity of the 
mouth, and to subject it again to the action 
of the grinding teeth, when it has escaped 
from between their surfaces. The muscles 
of this organ, which we have enumerated in 
the myological division of the article, give it 
a power of motion in every direction. 
But the simple act of mastication would 
only reduce the food into a powder, oratal! 
events into a dry mass, that could not be 
swallowed without great difficulty. To ob- 
viate this inconvenience, it is plentifully 
moistened with a watery fluid called saliva, 
and is thereby converted into a soft paste, 
which can be conveyed into the stomach 
with perfect facility. The source of this 
fluid is in several glandular bodies situated 
near the mouth, and sending excretory ducts 
which convey the secreted fluid into that 
cavity. As the jaws move, their muscles 
compress these glands, and squeeze the 
secreted fluid into the mouth. The tongue 
is constantly employed in bringing again 
under the action of the teeth those portions 
of the food which escape from between 
thCm ; and the closure of the lips prevents 
it from falling out of the mouth. 
The true salivary glands are three in num- 
ber, on each side of the head. The largest 
is placed in the space left between the ear 
and the lower jaw-bone ; and is called, from 
its situation, the parotid. Its duct pierces the 
middle of the cheek. The two others are 
placed under the tongue, and are called the 
submaxillary and sublingual. Their ducts 
join to open by a common orifice, at the 
side of the membrane called the frenum of 
the tongue, which ties the under surface of 
that organ to the inside of the lower jaw. 
Besides these large salivary glands, there 
are other small granular bodies, which pouf 
a mucuous fluid into the mouth ; these are 
named, according to their situation, glandulaj 
labiales, buccales, &c. 
The cavity of the mouth, in which the 
process of mastication goes on, is not a very 
extensive one. There is a small space left 
between the cheeks and the teeth extei- 
nally ; but within the teeth the tongue oc- 
cupies nearly the whole room. The upper 
boundary is formed by the palate or roof of 
the mouth, and the lower by the surface of 
the tongue. The mouth opens behind by 
a tolerably free communication, into a jnem 
