90 
and another rather within the lower eyelid. 
See figs. 12 & 14. 
A left eye with the eyelids cut in the middle, and 
the outer halves everted to show the orifices of the 
ducts of the lacrymal gland, into which hairs are 
inserted, 
The preceding description of the lacrymal 
gland and its ducts shows that the latter and 
the lower mass at least of the former may be 
readily wounded along with the upper eyelid, 
and that in Crampton’s operation for entro- 
pium, the lower mass of the gland, together 
with some of the lacrymal ducts, must neces- 
sarily be wounded, if the eyelid be cut through 
near the outer angle and to any height. In 
cases in which I have performed the operation, 
however, I have not observed any lacrymal 
fistula or other bad consequence follow. 
Tears.—Lacryme, Fr. Les larmes; Ital. 
Le lagrime; Germ. Die Thrénen. The lacry- 
mal secretion like the salivary appears con- 
stantly to flow, though in no greater quantity 
than is sufficient to moisten the surfaces of the 
conjunctiva. The derivative lacrymal organs 
are in this case equal to the removal of it; but 
when the tears are poured out in unusual 
quantity, as they are, like the salivary or uri- 
nary secretion as well as that of the skin, in 
certain affections of the mind, they run over 
the margin of the lower eyelids and drop down 
the cheeks. 
According to Fourcroy and Vauquelin there 
remains after evaporating the tears, about one 
per cent. solid substance, which consists chiefly 
of common salt and a yellow extractive matter 
perfectly soluble in water. Before drying, this 
appears quite similar to mucus. 
2. Derivative lacrymal organs. 
Previously to describing the passages by 
which the tears are drawn off into the nose, it 
will be advantageous to take a glance at the 
cipal ps groove and canal in which the prin- 
ci t of those passages is lodged. 
Dhascest groove Por the lodgement of the 
lacrymal sac. The lacrymal groove, sulcus la- 
crymalis, is situated at the fore part of the 
inner wall of the orbit. It is directed from 
above downwards, extending from the junc- 
tion of the frontal bone with the nasal process 
of the superior maxillary and with the lacrymal 
bone, on the one hand, and to the inner and 
lower angle of the margin of the orbit on the 
other. Here it funs into the osseous canal for 
the nasal duct. The lacrymal groove is pretty 
LACRYMAL ORGANS. 
a 
deeply scooped out, and is about eight-tenth 
of weifoace a and five-twentieths broad, _ 
The outer aspect of the nasal Era ft 
superior mt bone is divided by an 
cending ridge, the continuation of that form 
the lower margin of the orbit, into two 
faces. The posterior surface, which is 1 
narrower, forms the anterior half of the lac 
mal groove. The posterior half of the gros 
is formed by that narrow grooved part 
orbital surface of the lacrymal bone in front 
its vertical crest. The line of junction (5 
dylesis ) between the posterior margin of 
nasal process of the superior maxillary be 
and the anterior margin of the lacrymalr 
down longitudinally in the bottom of © 
-groove. _* 
The anterior margin of the lacrymal gro¢ 
formed by the ascending ridge subdividing t 
outer surface of the nasal process of the sw 
rior maxillary bone, is thick and rounded. T 
posterior margin, formed by the crest whi 
subdivides vertically the orbital surface of t 
lacrymal bone, is thin and sharp. a 
Inferiorly the crest of the lacrymal bor 
forms a small curved prolongation directed fo 
wards and outwards, which serves to form t 
commencement of the posterior wall of ft 
osseous canal for the nasal duct. The proce: 
which is called hamulus ossis lacrym a 
culates with the orbital plate of the super 
maxillary.* _ 
The osseous canal for the nasal duct.—Th 
osseous nasal canal, about half an inch | 
length, extends from the lower extremity of # 
lacrymal groove to the lowest meatus of th 
nose, at the anterior of which it open 
Its orifice is overhung by the anterior extrem! 
of the lowest spongy bone. The osseous nas: 
canal is directed a little obliquely from befo 
backwards’ and from within outwards. It i 
somewhat narrower in the middle than at eith 
extremity. It is compressed from within o1 
wards, hence a horizontal section is rathe 
elliptical than circular. 
e anterior and outer walls of the osse 
canal are formed by a groove inclined dow 
wards and backwards on the inner surface 
the body of the superior maxillary bone, t 
continuation of that on the nasal process whi 
contributes to form the lacrymal ve. I 
posterior wall of the canal is im great pa 
formed above by the hamular process of # 
lacrymal bone, where it articulates with 
orbital plate of the superior maxillary. “ 
lowest part of the posterior wall is formed | 
the meeting together of the lacrymal proe 
* In man the lacrymal bone does not alwa 
form a single piece, ‘* In a great numberof cas: 
says M. Rousseau, ‘‘ the lacrymal bone is fo 
divided into two unequal parts, even in aged 8 
jects. The larger contributes to form the inj 
wall of the orbit, the smaller is situated be 
and outside the preceding on the floor of the orbi 
its exposed surface does not measure more thi 
two millimetres in extent, but it dips under t 
vertical crest of the first portion, and contribu 
to form the lacrymal canal.” See ‘* Descript 
d’un nouvel os de la face chez homme,” A 
nales des Sciences Naturelles. Paris, 1829. 
ts 
