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this is true I think the recent work upon the spleen proves quite conclu- 
sively. Since sinusoidal or open circulation exists elsewhere, the old 
argument that the capillaries of the spleen are closed because the capil- 
laries of the rest of the body are closed, is no longer of any value. 
It remains still to be shown that in normal circulation through the 
spleen the solid elements of the blood are carried through the spleen 
sinusoids or pulp-spaces. It is well known that in higher animals but 
relatively few red blood dises are found in the pulp-spaces and that 
it is practically impossible to obtain natural injections of them. This 
fact, together with a mythical homogeneous membrane lining the capil- 
lary veins, is vy. Ebner’s strong argument in favor of a closed circulation 
in the spleen. Von Schumacher, who also believes in this elastic mem- 
brane, always finds blood in the pulp with the membrane intact 
In ease the blood passes through the pulp-spaces in its normal cirecu- 
lation, it should be possible to retain it in them by making the proper 
experiment. Sokoloff and Wicklein made numerous experiments which 
appeared to prove that after ligature of the splenic vein the blood first 
accumulated in the veins, then the pulp becomes oedematous, after 
which the blood elements pass over into the pulp. No doubt all of 
these observations are correct, but it appears to me that their reasoning 
is wrong, as Weidenreich has shown recently. Sokoloff states that as a 
rule the normal spleen contains no blood within it, and it is difficult to 
find it even in the blood-vessels (p. 211). This is due to the contraction 
of the muscle, which always takes place when the organ is removed and 
presses the blood out of the spleen (p. 213). ‘“ Wie wire es denkbar, dass 
bei einer solechen Ueberfiillung der Venen, die Pulpa nach dem Tode ihr 
Blut in die Venen entleeren sollte. Wenn der Blutstrom unter normalen 
Verhiltnisse aus der Arterie in die Milzpulpa und von da in die Venen 
sich ergiessen wiirde, musste hier effenbar die Pulpa mit Blut tiberladen 
erscheinen,” etc. (p. 215). 
In addition to this Sokoloff showed that the walls of the capillary 
veins are very porous, in fact wanting around the Malpighian follicles, 
and it was through these pores he thought that the blood passed into 
the pulp in case the vein was closed long enough. 
Wicklein repeated the experiment of Sokoloff and found that if the 
vein was ligated long enough to produce an extensive infarction of the 
pulp this infarction would disappear in the course of time in case the 
ligature was removed. In all cases he ligated the vein for 30 minutes, a 
time sufficiently long to cause an extensive distention of the pulp with 
blood, then he removed the ligature and killed the animals in from 4 
hours to 21 days, and in all cases found the pulp normal in every respect. 
