s LACRYMAL ORGANS. 
perior fork, however, has a few of its fibres 
ended with the ciliaris.” 
The action of the muscle appears to be to 
rect the lacrymal papille and points in to- 
ards the lacus lacrymalis, and to assist in 
eping the edges of the eyelids properly ad- 
_ justed to the eyeball. 
| WNerves.—The parts of the organ of vision 
which have been just described receive their 
ves from the fifth and seventh pairs; the 
her communicating sensibility, the latter the 
power to move. See articles, FirrH Pair oF 
PRVES, and SEVENTH PAIR OF NERVES. 
The first division of the fifth pair gives 
nerves not only to the accessory parts of the 
ye, but oo Ane also the eyeball ; hence it is 
illed ophthalmic. The second division of the 
th sends filaments to the lower eyelids. 
Nerves from the first division of the fifth 
| distributed to the accessory parts of the eye — 
' The first division of the fifth pair or the oph- 
thalmic divides into three nerves, the,fron- 
‘al, the nasal, the lacrymal. 
1. Frontal nerve. The supra-trochlear 
branch of this nerve gives filaments to the 
upper eyelid and inner canthus. The continu- 
ation of the frontal nerve sends filaments to the 
upper ary and external canthus. 
2. Nasal nerve. The infra-trochlear branch 
of this nerve supplies the parts at the inner 
panthus, the conjunctiva, the lacrymal caruncle 
and lacrymal sac ; it also gives filaments to 
the orbicularis palpebrarum. The tensor tarsi* 
eceives two twigs from it. The infra-trochlear 
sends branches upwards, which anastomose 
with those of the supra-trochlear. 
3. Lacrymal nerve—After supplying the 
lacrymal gland the branches of this nerve 
emerge from it, and ramify in the conjunctiva, 
rbicularis muscle, and skin of the eyelids. 
e lacrymal nerve forms anastomoses with 
ther branches of the fifth. 
Nerves from the second division of the fifth 
Pair distributed to the accessory parts of the 
é.—The principal of these is the inferior 
alpebral branch of the infra-orbital. The in- 
rior palpebral nerve divides into two branches, 
h external and an internal, which indeed 
"tay be separate from the first. 
The external branch runs in the substance of 
the lower eyelid, distributing branches in its 
Course, to the outer canthus, where it anasto- 
noses with the inferior palpebral filaments of 
the lacrymal nerve. 
|_ The internal branch supplies the part of the 
ower eyelid towards the nose, and terminates 
‘in the parts at the inner canthus, anastomosing 
_ with a branch of the infra-trochlear. 
The facial or portio dura of the seventh pair. 
Of the accessory parts of the eye, the orbi- 
tularis muscle is that which receives branches 
from the portio dura of the seventh pair; per- 
ier, also, the tensor tarsi muscle, as Mac- 
¥ 
2 * Rosenmiiller, Icones chirurgico-anatomice. 
eimar, 1805. 
Trasmondi, Intorno la Scoperta di due Nervi 
Il” Occhio umano ragguaglio. Estratto dal Gi- 
ale Arcadico, t. xix. p. T Roma, 1823, 
93 
kenzie conjectures. These branches of the 
portio dura freely anastomose with the branches 
of the fifth pair above described. 
To this superficial notice of the nerves of 
the accessory parts of the eye described in this 
article, all that requires to be added is, that the 
levator palpebre superioris receives its nervous 
filaments from the third pair. 
Bloodvessels.—1. Arteries.—The branches of 
the external carotid ramified on the face and 
the ophthalmic artery from the internal carotid 
are the sources from which the accessory parts 
of the eye receive their arteries. 
The branches of the external carotid in the 
face, viz. the facial, the infra-orbital of the in- 
ternal maxillary, the transverse artery of the 
face and the temporal send ramifications to the 
eyelids. Towards\the inner canthus the facial 
ends in the angular artery, which anastomoses 
with the nasal branch of the ophthalmic. The 
angular artery, or some one of its branches, is 
implicated in the operation for fistula lacry- 
malis as it is called. 
The ophthalmic artery gives off the acrymal, 
usually one of its first branches after its en- 
trance into the orbit. The lacrymal supplies 
the upper and lower masses of the lacrymal 
gland, besides other parts in the orbit, and at 
last issues from that cavity at the external 
angle of the eye. The muscular arteries of the 
ophthalmic, after supplying the recti muscles, 
are continued forward on the front of the eye- 
ball—one from the external rectus muscle, and 
two from each of the other recti. These arte- 
ries divide into two sets of branches, of which 
one set ramify in the ocular conjunctiva, and 
the other set supply the sclerotica. 
The ophthalmic, as it issues from the orbit at 
the internal canthus, gives off the palpebral 
arteries, superior and inferior. These ramify, 
in their respective eyelids, towards the external 
angle, where they meet and inosculate with the 
terminating branches of the lacrymal artery. 
The superior palpebral artery, moreover, inos- 
culates with the supra-orbital and anterior tem- 
poral ; the inferior palpebral artery with the 
nasal branch of the ophthalmic, the infra- 
orbital and transverse artery of the face, thus 
forming the tarsal or palpebral arches. 
The ramifications sent, from. the branches of 
the external carotid in the face, to the eyelids, 
and those from the ophthalmic, form by their 
inosculations a network, from which are sup- 
plied the different structures of the eyelids, the 
conjunctiva, the lacrymal caruncle, and ‘the 
lacrymal sac. 
Where the ocular and palpebral portions of 
the conjunctiva run into each other, bloodves- 
sels from the muscular enter and subdivide into 
two sets of branches—one set smaller, to the 
ocular conjunctiva, the other set larger, to the 
palpebral conjunctiva. The latter receives 
another and a still larger set, which enter it at 
the orbital margin of the tarsal cartilages, 
anastomose with the first set, and ramify for- 
wards to the free margin of the eyelids. 
The bloodvessels of the ocular conjunctiva 
are few and small in comparison to those of 
the palpebral. They atlect a reticular arrange- 
