THE THYMUS GLAND. 
50T 
Healing the Wound. —We will suppose that the desired effect 
has been produced. Time has been allowed for removal of the 
obstruction, or the subsidence of inflammation, and we wish again 
to close the artificial aperture. Nothing is so easy. We lightly 
scarify the cellular and muscular substance beneath, and the in¬ 
side of the integument; we bring the lips of the wound neatly 
together, having previously scarified or pared them ; we confine 
them by a suture; we place a little dry tow over the wound, and 
confine it by a loose bandage: and not only will the external 
wound be healed in a few days, but in prooess of time, as you 
see in this specimen, the cartilage will be reproduced, and the 
trachea be as perfect as ever. 1 need not caution you, I think, 
that in extensive inflammation of the aerial passages, or in 
inflammation of the lining membrane of the trachea itself, al¬ 
though attended with difficulty of respiration, and that almost 
threatening suffocation, this operation would be more likely to 
increase the inflammation than to produce a beneficial effect. 
THE THYMUS GLAND. 
Well, gentlemen, we once more trace the entrance of the 
trachea into the thorax, and it has scarcely penetrated between 
the first ribs ere, in a young subject, it comes in contact with an 
irregular glandular body situated in the doubling of the anterior 
mediastinum. This is of a pale pink colour, and of a tabulated 
structure like that of the salivary and pancreatic glands. It is 
the thymus gland, or in vulgar language, the sweetbread. 
Its progressive Development. —In the early period of utero- 
gestation, it is of very inconsiderable bulk, and confined mostly 
to the chest, but during the latter months it strangely develops 
itself. The superior cornua protrude out of the thorax ; climb up 
the neck between the carotids and the trachea ; are evidently con¬ 
nected with the thyroid glands, and become parts and portions of 
the parotids. The parotid and the thymus glands are, in the 
latter months of foetal life, essentially the same ; composed of a 
multitude of granules arranged into lobules, which are of greater 
or less size, and enveloped by slight and easily lacerable mem¬ 
branes. When they are cut into, a milky fluid is observed in 
both, the composition of which has not, I believe, yet been exa¬ 
mined. They cannot be dissected from each other; the one is a 
prolongation of the other, and the only difference in them is, that 
the parotid duct can be traced into the mouth, but no duct has 
ever, that l am aware, been traced in the thymus gland. 
Identified with the parotid. —Here is a beautiful dissection of 
it. Prolongations of the thymus, and those of considerable sub- 
