ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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a conspicuous object, and may be readily removed. After removal it 
must be slit open, so that the inner surface shall lie upward toward the 
objective. To do this, my plan is with great care to insert a line needle 
into the lumen, the cavity of the intestine, and when the tube has been 
placed on the steel without haviug its wall pierced at any point, it is 
gently rubbed with another needle until it is slit from end to end. This 
is not a difficult thing to do if the needle be fine and the microscopist’s 
hand be steady. Alter the intestine, or a part of it, has been taken from 
the body, all subsequent manipulations may and should be performed 
on the slide and in the cell in which it is to be mounted. 
The intestine, slit open, is then placed in a small drop of water, and 
while it still remains attached to the needle is to be gently freed by 
another needle and floated in the water, inside upward. The intestinal 
contents are then to be washed away by the repeated dropping of water. 
When thoroughly cleaned, as may be known by the disappearance of all 
the brownish fasces, drain off the water and add one or two drops of a 
solution of methyl-green, one of the anilin stains to be had of the dealers 
in microscopical supplies. The dye acts rapidly, so that from four to 
five minutes will usually be long enough to colour the parts sufficiently. 
Wash away the superfluous stain, drain off the water, add a drop of 
diluted glycerin and apply the cover-glass, cementing it in place with 
shellac. 
A small piece of the intestine is all that is needed ; it is not necessary 
to take the entire intestinal tube. I have found the rectum, the posterior 
region nearest the external aperture, to be free from faecal matter, and 
beautifully transparent. In this part, too, the cells may be rather better 
displayed than in auterior regions. The cells are comparatively im- 
mense, with conspicuous cell-walls, prominent nuclei with their inclosed 
nucleoli, and with the structure of the protoplasm finely disjdayed. The 
latter may be seen well with a good 1/5-in. objective, but of course with 
greater satisfaction under a lens of higher power. 
A close, small meshed network of the protoplasm does not seem to 
be a constant and invariable feature of its structure, although in many 
cells it is exquisitely demonstrable, while in many others it is composed 
of exceedingly fine fibres radiating in every direction from the centre 
toward the cell-wall and forming meshes so narrow that they are very 
inconspicuous, really demanding somewhat careful search to see them. 
Here the fibrillated structure dominates, and this appearance calls to 
mind the aspect of an almanac sun, the face of the symbol being here 
represented by a somewhat irregular nucleus, with fine rays increased 
to an indefinite number. 
While examining these large and beautiful cells the observer should 
bear in mind these two appearances, and not be disturbed if the network 
is not as plainly visible and the meshes as close, small and regular as 
he expected they would be. In my experience the fibrils are the most 
readily demonstrated, unless a very high power, a 1/12 or higher, be 
used to study the protoplasm surrounding the tubule of the nucleus 
and situated between it and the membrane including the nucleus and 
separating it from the protoplasmic contents of the cell. In this part 
of the object the reticulum, or network of delicate fibres, is superbly 
demonstrable. 
