LYMPHATIC AND 
_ the chyle is supposed to enter by imbibition. 
This incipient net-work of lacteals terminates at 
the roots of the villiin branches, which perforate 
the muscular coats of the intestines, the trunks 
of which may be easily distinguished under 
the serous coat, taking a transverse course to 
gain the cellular interval between the layers of 
the mesentery. These are what may be termed 
the deep-seated lymphatics of the intestines 
which alone contain the chyle, but there are 
superficial lymphatics belonging to the intes- 
tines situated immediately under the peritoneal 
coat, which take a longitudinal course and 
join the deep-seated vessels. From the intes- 
tine the principal branches pass in nearly 
straight lines between the layers of the mesen- 
_tery, where they traverse the mesenteric glands 
to accumulate from every portion of the small 
intestine around the trunk of the superior 
mesenteric artery. The lymphatics from the 
cecum, the ascending and transverse colon, 
which have passed through their appropriate 
glands and have accompanied more or less the 
ilio-colic and colic arteries between the layers 
of the meso-colon, now join the lacteal vessels. 
The vasa efferentia from the mesenteric glands 
form two or more trunks, which, conducted 
by the root of the superior mesenteric artery, 
reach the thoracic duct, into which they empty 
their contents just above its commencement. 
The lymphatics of the stomach chiefly 
accompany the bloodvessels. ‘Those associated 
with the vasa brevia and with the left gastro- 
epiploic vessels, having passed through their 
glands unite with the lymphatics from the 
spleen. Those accompanying the right gastro- 
epiploic vessels having traversed their glands 
communicate behind the pyloric extremity of 
SEieeel 
the stomach and at the commencement of the 
duodenum, with the lacteals, and with the 
lymphatics from the liver. At the upper cur- 
vature of the stomach, the lymphatics take their 
course from the cardiac to the pyloric orifice 
accompanying the branches of the coronaria 
yentriculi arteries, they pass through the glands 
there situated, and join the lymphatics descend- 
ing from the liver in the capsule of Glisson. 
The lymphatics of the pancreas near the 
head of the organ communicate with the lacteal 
vessels from the duodenum; the rest empty 
themselves into the lymphatics coming from 
the spleen. 
_ Atthe hilum of the spleen the deep-seated 
lymphatics which have accompanied the blood- 
vessels in the substance of the organ are joined 
by the superficial vessels. The principal 
branches having in their course received lym- 
citi from the stomach and pancreas, and 
aving traversed the splenic glands, accompany 
the trunks of the splenic artery and vein, and 
unite with the lymphatics of the liver in their 
course to the thoracic duct. 
The deep-seated lymphatics of the liver 
accompany the ramifications of the portal 
vessels throughout the substance of the organ ; 
they emerge with the hepatic ducts at the 
_ transverse fissure of the liver, where they are 
_ joined by the lymphatics of the gall-bladder 
and by the superficial lymphatics from the 
LACTEAL SYSTEM. 229 
under surface of the liver. They pass through 
the glands situated in the capsuleyof Glisson, 
receive free communications front the splenic 
and gastric lymphatics, and ultimately termi- 
nate in the thoracic duct either separately or 
in conjunction with the lacteal trunks. 
The superficial lymphatics of the upper 
surface of the liver form three or four fasciculi, 
which enter the thorax without joining the 
trunks of the deep-seated vessels. One set 
streams from the upper surface of the right, 
another from that of the left lobe to gain the 
suspensory ligament of the liver, between the 
folds of which the larger branches, six or eight 
in number, pass upwards and enter the thorax 
between the attachment of the diaphragm and 
the ensiform cartilage to gain the anterior 
mediastinum, where they join the large lym- 
phatic vessels accompanying the arterize mam- 
marie interne. From the right and left lobes 
in the neighbourhood of the lateral ligaments, 
and chiefly, though not entirely, from the 
upper surface of the organ, two other streams 
of superficial lymphatics tend towards the 
lateral ligaments, between the layers of which 
the principal branches pass. They perforate 
the diaphragm to gain its upper surface, some 
of them passing backwards to reach the thoracic 
duct in the posterior mediastinum, while others 
form a large vessel which creeps upon the 
thoracic surface of the’ diaphragm under the 
pleura and near the margin of the ribs, to gain 
the anterior mediastinum, where on each side 
it unites and terminates with those vessels 
which have arrived at the same point from 
between the folds of the suspensory ligament. 
The lymphatics of the left lateral ligament 
often, however, pass downwards to the abdo- 
minal cavity, joining the lymphatics of the 
under surface of the liver or of the cardiac 
extremity of the stomach. 
The thoracic duct receives but four branches 
during its passage through the thorax; the 
lymphatics of the lungs and of the heart, as well 
as the large branches accompanying the mamma- 
riz interne vessels, make their exit from the 
thoracic cavity, to empty themselves into the 
two lymphatic trunks in the cervical region. The 
intercostal lymphatics accompanying the inter- 
costal bloodvessels, traverse the little glands si- 
tuated near the necks of the ribs, take their 
course to and enter the larger glands in the pos- 
terior mediastinum. These same glands also 
receive the cesophageal lymphatics, and even 
some communications from the bronchial 
glands ; their vasa efferentia, four or five in 
number, enter the thoracic duct at different 
levels. 
The large lymphatics accompanying the mam- 
marie interne arteries collect their branches 
from various sources; those from the liver have 
been already noticed ; some pass through the in- 
tercostal spaces close to the edges of the ster- 
num: some have accompanied the intercostal 
branches of the mammariz interne vessels; 
others are received from the thymus gland and 
pericardium and pleura. The greater part of 
these vessels pass through the little glands si- 
tuated in the anterior mediastinum before they 
