perforate the wall of the vein and pass 
through it, if not with the whole body, at 
least with the anterior part, also the position 
of the genital opening and the analogy 
with other worms suggest this idea. The 
very endophlebitis speeks for it, as it is al- 
ways excentric (even when almost oblite- 
rating) and thus indicatesa localized lesion. 
It is true that this process of oviposition 
has not been witnessed in the preparations, 
as far as the literature and my experience go, 
but neither has the oviposition in the vein. 
It is easier to unterstand how the eggs, 
which are so often seen at the base of the 
mucosa, may come to the surface, though the 
bloodstream in the veins and the iymphcir- 
culation go in the opposite ‘direction. They 
generally follow the tissue between the glands 
of LIEBERKUEHN and donot pass through 
them (as the preparations clearly show). The 
only force acting in this direction is the re- 
constitution of the tissue. No abscess forma- 
tion helps the elimination and the ulcerations, 
when present, are quite superficial. 1 cannot 
share the opinion of LETULLE, who thinks 
that the dilated and sometimes suppurating 
glands, help the escape of eggs and miraci- 
día, nor can I admit that all the living eggs 
should have passed through the warty or pe- 
dunculated adenoms which are found in old 
cases. They are more likely to be the source 
of the degenerated and calcified eggs which 
are abundantly found in the stools of certain 
cases. 
As for the eggs, seen inthe submucosa 
and under theserosa of the intesiine, in the 
liver, pancreas, brains and lungs, they mostly 
fail to reach the surface in a living state, as 
long as the host is alive. They accumulate in 
the tissues, where they are seen in great 
numbers, and, after provoking during a short 
period an inflammatory reaction, they finally 
are incapsuiated in a cicatricial tissue without 
a sign of reaction. Calcification sets in after 
an indeterminate, but probably very long, pe- 
riod and may indicate the final death of the 
egg. 
Living eggs are not known to have been 
128 
found in the bile or pancreatic secretion. I 
examined the contents of the gallbladder se- 
veral times with constantly negative results. 
In sections the eggs are never seen in the 
bile ducts. 
Other worms are known to deposit their 
eggs in the tissues of their hosts, for instan- 
ce the Hepaticola hepatica, the eggs of which 
are very common in the liver of the common 
rat and have often been taken for coccidia. 
In this case it is quite sure that they are de- 
posited by the adult worm which afterwards 
dies in the same place. The eggs do not 
reach the outside world, unless the host is 
eaten by any animal or dies in some other 
way. 
Besides living eggs in their earlier sta- 
ges and calcified ones, the tissue may contain 
empty shells, as the typical form of the tear 
and giant cell formation clearly show. They 
are found in different situations and not only 
near to LIEBERKUEHN’S glands, as might 
be supposed from LETULLE’S description, 
who considers the escaping ofthe miracidium 
by the holiow space of the gland as a nor- 
mal way of spreading the infection. We may 
state that neither he nor anybody else ever 
saw a free embryo in the sections. In my 
opinion it is extremely unlikely that miraci- 
dia, escaping from the eggs in the tissues, 
should pass through the intestine alive and, 
even so, they would die soon, unless they 
came immediately in contact with water. I 
cannot believe that the rather rare ocurrence 
of ecdysis in the tissues is of any advantage 
for the propagation of the flukes, but the 
fact is very interesting and hard to explain. 
Undoubtedly in the infection with schi- 
stosoms as well, as with many other worms, 
there is an enormous waste of eggs which 
in our case is not even compensated by a 
large production. The real compensation is 
given by the enormous multiplication in the 
organisms of the infected snail. 
In the larger number of cases the ripe 
eggs appear mixed and in close contact 
with the common elements of the stools and 
not involved in bloody mucus. This constant 
