1887. ] MICROSCOPICAL JOURNAL. 185 
follows it everywhere. Upon the right side of this body there lies a second, 
like the first in shape but altogether unlike it in appearance, for the elongate 
space runs into it and along it part way and then stops, while the boundary 
substance fills the entire body except at the tip, where a very small space may 
be seen. On the left of our first body a third one is seen resembling it, 
but shorter than it, and on its left a third, with two spaces, one at each end, 
and entirely disconnected from ‘the central space A in the section. These 
facts, taken in conjunction with our observation of the gross anatomy of the 
‘liver,’ will permit of but one interpretation. The space A is the main duct 
of the gland lobe; the space B is the duct of one tubule cut along the entire 
length of the tubule, blind at one end and opening into the main duct at the 
other, and the other projections from A are other ductules which have been 
cut across before their end was reached as they passed out of the plane of the 
section. In some cases the sections are obliquely across or square across the 
tubules, and in those cases the space is elongate or not, but in either case are 
- entirely surrounded by the boundary substance, which is the glandular epi- 
thelium. 
The glandular epithelium is sometimes seen in cross-section and sometimes 
as at E, and in the tubule backing the ductule before mentioned in horizontal 
section, which gives a surface view. 
3. The blood space and the contained corpuscles may be seen every- 
where dispersed through the section, but everywhere showing the same rela- 
tion to the lumen of the gland as was observed in the green gland,* namely, 
the lumen of the duct and the blood space are everywhere separated from 
each other by the glandular epithelium, and cannot connect except through 
this wall of cells. The blood spaces, however, surround every tubule, as 
evidenced by the sections, so that everywhere the tubule is bathed in blood. 
How does the blood get through the capsule if it completely surrounds the 
gland lobe? The way in which this entrance of the blood through the cap- 
sule and into the spaces is not shown in sections prepared after this manner. 
4. The foreign body.—lIt is not by any means infrequent to find in all 
parts of cray-fish livers small black spots, which are among the tubules. 
They are readily seen by the naked eye and are larger than the tubules. 
In sections of the liver one often chances upon these bodies, which are no 
part of the normal liver, but which do not appear to exercise any malign 
influence upon the organ. They are seen to be independent of the tubules 
and imbedded in the body space within the contour of the gland. Neighbor- 
ing tubules are uninfluenced by them to all appearances. Each such body is 
surrounded by a thick-walled cyst, and upon this there is to be seen a thick 
mass of corpuscles investing it. Within the cyst a body is seen which, when 
treated as these sections were, is a structureless, finely granular, scarcely 
staining mass, of a character not as yet determined. What its real character 
is is an interesting question for further study, but need not be answered at 
present, as it does not directly concern the minute anatomy and histology of 
the cray-fish’s liver. 
5. Summary of minute anatomy.—We are now prepared to definitely 
state our idea of the anatomy of the liver of the cray-fish, which we may do 
somewhat as follows :—It is a paired three-lobed body, made up of numerous 
tubes, blind at one extremity and opening at the other into a main duct; this 
in turn opens into a duct in common with two other main ducts, and the 
principal or common hepatic duct opens into the alimentary canal. We have 
still to examine into the cellular structure of the hepatic epithelium and to 
make a comparison between the liver and the green gland. 
[ Zo be continued. | 
* See above, p. 125. 
