172 
vessels, and in those of the excreting ducts and 
gall-bladder; the lobules were coloured with 
the blue injection; the red was confined to 
their circumference, and appeared in points 
only. This experiment was varied by inject- 
ing the portal vein and its branches as far only 
as the entrance of the latter into the lobules, 
the lobules thus remaining uninjected. The 
injection propelled through the arteries had 
now free access to the uninjected lobules, and 
no exit by the injected portal vein; and the 
artery having no communication with the he- 
patic veins, the injection had no exit by these 
vessels: the lobules however were not better 
injected in this than in the preceding experi- 
ments. From these experiments I conclude, 
that the secreting part of the liver” “is supplied 
with arterial bl for nutrition only. As all 
the branches of the artery of which we can 
ascertain the termination, end in branches of 
the portal vein, it is probable that the lobular 
arteries terminate in the lobular venous plex- 
uses formed by that vein, and not in the intra- 
lobular branches of the hepatic veins, which 
cannot be injected from the artery.” Miiller, 
who published upon this subject previously to 
the discoveries of Kiernan, and was therefore 
not aware of the exact distribution of the ves- 
sels, was deceived by this free communication 
between the hepatic artery and portal vein. 
He conceived, with the older anatomists, that 
the arterial blood was mixed with the venous 
blood of the vena porte, ina capillary network, 
“vascula ultima reticulata,” common to the 
three bloodvessels of the liver, the hepatic ar- 
tery, portal vein and hepatic veins. Observing, 
moreover, in the injected preparations of Lie- 
berkiihn,* that the “ vascula ultima reticulata,” 
the lobular venous plexus of Kiernan, appeared 
as well filled when the injected fluid was 
forced into the hepatic artery, as when intro- 
duced through the portal or hepatic vein, he at 
once decided that the artery must pour its blood 
directly into this plexus. Hence he writes, 
* Vascula ultima reticulata sanguinem tam ab 
arteriis quam a vend portarum accipere, ve- 
nisque hepaticis reddere, ex hisce argumentis 
concludo: Post injectionem in arteriam hepa- 
ticam non minus quam in venam portarum aut 
venas hepaticas factam, eadem communia vas- 
culorum minimorum retia replentur, quod ex 
injectionibus exsiccatis Lieberkiihnianis, Bero- 
lini asservatis, facile quisquis sibi persuadebit.” 
Having recourse himself to an extremely im- 
perfect experiment, the injection of water into 
the hepatic artery, and finding that this fluid 
returned by the portal vein, and possibly by the 
hepatic vein, he became convinced of the com- 
munications of all the vessels in the “ vascula 
ultima reticulata,” and added another argument 
to the injections of Lieberkiihn in favour of 
his opinion; for he says, “ Injecti liquores co- 
* Having, through the kindness of Mr. Liston, 
had an opportunity of examining with the micro- 
scope some of the injections of Lieberkiihn of dif- 
ferent tissues, I can bear testimony to their beauty 
and wonderful minuteness, and can fully appre- 
ciate the deservedly high estimation in which they 
are held among the physiologists of Germany. 
NORMAL ANATOMY OF THE LIVER. 
lorati ex alio vasorum ordine facile in al 
transeunt, qualis frequens Halleri veteram 
Walteri, denique et Rudolphi cel. extat e 
rientia. I equidem transitum 
pide et colorate sepius observari.” Noy 
regard to the injections of Lieberkiihn, I 
only repeat with Kiernan, that if the lob 
venous plexus or “ vascula ultima 
were filled, actually, from the 
only route which the injection could 
taken must have been through the capil: 
the excretory ducts and vasa vasoram, and 
through the portal vein. But with re; 
the water experiment, I am quite 
its utter inadequacy to elucidate so delic 
pot as that under discussion. In 
experiments, made with a view of assuri 
self of the nature of these plexuses, I hay 
been content with my injection unless I 
distinctly trace with the aid of the mi 
each capillary vessel from the interlobulat 
to the intralobular vein, and this I have 
failed to do in a successful injection 
abet vein; or in the opposite course whe 
epatic veins have been filled. But in 
most successful injection from the artery, 
the capsular arteries have been beautife ly 
I have never observed more than a 
are in the circumference of ok 
here is, however, in the consideration 
question, one circumstance which apps 
have been altogether overlooked by 
but which seems to me to be fatal to the o 
which he entertains with regard to the dis 
tion of the arterial blood. e ducts at 
dantly supplied with blood from the 
indeed to so great an extent, that in a 
injected liver their coats appear to consist ¢ 
wholly of the ramifications of minute ve 
Now if the aggregate of the surface form 
the ducts, which is thus covered with ¥ 
supplied from the artery, be considered, it 
be evident that very httle can be left for 
“vascula ultima reticulata.” And if 
jointly with this fact, the difficulty of inje 
the lobules from the artery be consid 
must be admitted that Miiller carries hisd 
somewhat too far, in asserting without li 
tion “that the arterial blood of the he 
artery and the venous blood of the port 
come mixed in the minute vessels of the 
The hepatic veins return the whole of t 
nous blood from the liver to the general 
circulation. They commence in the cei 
each lobule by means of a small vein 
intralobular, which collects the blood 
circulation through the lobular venous p 
The intralobular veins pour their curren! 
the sublobular veins, and these latter ur 
form the hepatic trunks, which 
inferior vena cava. The hepatic differ fro 
portal veins in being more immedi 
tact, and more closely connected with the 
stance of the lobules. Thus the intralo 
veins are embedded in the substance of ¢ 
lobule, and the sublobular inclosed in ¢ 
formed by the bases of the lobules, and th 
fore by that part which is uninvested b 
lobular capsule. The hepatic trunks 
= 
ol 
nig 
rhe 
* 
PTTInNALe 
