734 
of the facial artery, for they are usually larger 
than the angular artery, which is given off as a 
branch from one of them. They chiefly supply 
the skin and muscles; they form a complete 
network over the nose, and those of one side 
anastomose freely in the middle line with those 
of the other. Many of their branches also 
pass between the cartilages or turn in at the 
nostrils and supply the anterior part of the 
mucous membrane. 
_ _ The veins of the nose, so far as they are 
known, are associated with its arteries. Their 
communication with the veins within the skull 
has been already mentioned. The anastomosis 
is chiefly effected by means of the branches of 
the ethmoidal and aphenc- palatine veins, which 
communicate with branches opening into the 
longitudinal and coronary sinuses. 
The lymphatic vessels of the nose have not 
been particularly examined. Cloquet says 
their principal trunks accompany the blood- 
vessels and go to the jugular ganglia. 
Developement of the nose—The develope- 
ment of the nasal cavities lays, as it were, the 
foundation for the construction of the face.* 
They are first formed as a kind of canal, whose 
lateral walls are chiefly composed by the ante- 
rior and lateral frontal processes of Reichert— 
those processes which grow out from the sides 
of the covering of the first cerebral vesicle 
(Stirnkappe ), in front of the first visceral arch. 
This canal has on its outer side and behind it 
the rudimental substance for the upper jaws, 
(the superior maxillary processes of Reichert,) 
and above it the base of the skull and the 
origins of the first pair of visceral arches thence 
arising. As the upper jaws grow with a rapi- 
dity far exceeding that of the growth of the 
frontal processes, they come at last to form 
alone the lateral walls of this canal, while the 
frontal processes form its inner walls; and, 
together with those changes, the canal becomes 
deeper, and its external apertures, which at 
first lay at the sides of the head between the 
two frontal processes of each side, approach 
the median line, and assume a lower position. 
After this, as the upper jaw of each side, con- 
tinuing to grow inwards, approaches that of 
the opposite side, they at length unite to form 
the palate, and thus separate the common ca- 
vity, which at first existed, into an oral and a 
nasal cavity. 
Of the parts just mentioned, the anterior 
frontal process is regarded by Reichert as the 
basis in which the nasal bone is developed ; 
and the lateral frontal, or naso-frontal process 
as the basis for the lachrymal bone. The supe- 
rior maxillary bone appears to be developed in 
the part named after it; the intermaxillary bone 
in a portion of the anterior frontal process, or 
its junction with the superior maxillary pro- 
cess; the palate bone and the pterygoid pro- 
cesses in the upper part of the first visceral 
arch. 
The formation of the parts within the nasal 
cavities is, he says, thus effected: within the 
* Reichert, Ueber die Visceral-bogen, Miiller’s 
Archiv. 1837, pp. 144 and 159. This account is 
drawn from the developement of the Pig. 
. 
NOSE. 
formative substance enclosed between the walls 
of the one rudimental cavity two cartilages 
form; one of these is the prolonged cartila- — 
ginous body of the first cephalic vertebra which _ 
forms the septum of the nasal cavities, and m 4 
be traced without any breach of continuity to 
their outer orifice, where it ends membranous 
in the adjacent formative mass. The other — 
cartilage is double, and appears somewhat — 
later than the preceding, on each side of which 
it lies close to the lower of the first ce- — 
phalic vertebra, with an arched surface directed — 
outwards to the eye. Each of these second, or 
lateral cartilages becomes the cellular portion — 
of the ethmoid bone, the lamina wee 
and may be easily separated from the vertebra 
and its visceral arch, from which its formation 
is entirely distinct. Even for some time after 
they are ossified this separation may be effected — 
without injury to the surrounding parts; but at 
a later period they completely coalesce. J 
ossification of the septum takes place later than” 
that of the other bones of the face. In all 
Mammalia it makes progress from the base of 
the skull downwards and forwards, and in all a 
part of the septum in front and below is left 
unossified ; so that divisions are produce 
which had originally no existence. The vome 
Reichert thinks, is formed separately when thi 
SESE portions of the superior maxillary 
nes meet together. a 
The olfactory nerve is originally, like th 
optic and auditory nerves, a kind of vesicu! 
or tubular prolongation from the medulla 
tube which constitutes the cerebro-spinal as 
of the embryo. According to Valentin,* — 
proceeds from the most anterior A > of t 
tube, that is, from the foremost of the thi 
embryonic cerebral vesicles; but, according — 
Reichert, from the lower and front part of t 
side of the second of them. Von Baer+ fo 
the olfactory nerves presenting this vesicul 
form in the chick during the third day of 
cubation; they projected from the lower surf 
of each hemisphere into the formative ti: 
of the skull, and exhibited a small round | 
lucid surface bordered by a dark circle. Rat 
observed similar appearances in the sheep” 
adder. The interior of the vesicle is li 
according to Valentin, by a delicate ci 
epithelium. Anteriorly it appears to termi 
at the end of the olfactory bulb; posterior 
is continuous with the anterior part of 
lateral ventricles of the cerebrum. 4 
The early developement of the haman 
has not been particularly studied, but is 
bably very similar to that just described 
observations in the lower animals. 
i, 
Ina 
formed embryo an inch in length, I have 
the nasal cavities of etsaeiooe large 
On their lateral walls they present distinet 
of the rudiments of the two lower tarb 
bones in prominent horizontal folds of the 
membrane. The palate is at this time! 
only anteriorly and at its sides ; its midd 
tion is widely open, exposing to the 
* Soemmering, I. c. p. 404. 
+ Quoted in Bischoff, Entwickelung: 
(Soemmering, Vom Baue, &c. B. viii.) 
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