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cell contents as convenient, by washing with a piece of 
sponge and acetic acid or ether, rubbing lengthwise with 
pulp. This will show more clearly the septum of filaments, 
and also show the countless openings through the pulp mem- 
brane, where the fibrils pass out into the dentine. These 
specimens will not keep well for permanent use, unless 
mounted in pitch on both sides; even then changes take 
place. 
Formula No. 5. Fresh pulps may be dissected into small 
patches, or torn to pieces and mounted as above directed, 
which will show more or less of the structure of the interior 
of the pulp ; patches of nerve fibres or filaments may be 
seen intact. 
Formula No. 6. Remove fresh pulps and let them dry a 
day or so ; then with a short pointed bistoury or scissors split 
open the pulp from end to end, and spread out on coated 
glass as before directed, mount and label. In these speci- 
mens the openings through the membrane may be distinctly 
seen, also the system of nerves as heretofore described in 
former articles, though not entirely intact, but more or less 
distributed. The above are the leading features of preparing 
pulps for the microscope, though many other methods may 
be employed, none of which will be entirely satisfactory to 
the beginner. 
In the case of dried pulps, they may be put into water and 
swelled, then split open, dissected, and examined. 
A new set of formulas will now be given, which will show 
the filamental system to perfection and in situ, and, cell 
structures and blood vessels generally being obliterated by 
differentiation, only in some instances the vessels may be seen 
with their contents. As we lack terms to fully describe this 
process, I will suggest something new, as ossification and 
calcification neither are expressive. Dentification, which is 
in use, and the most satisfactory, does not fully give the pro- 
cess ; instead, I would suggest the terms dentificatio pulpce 
or dentum secundum, meaning secondary dentine. Another 
form of hardened pulp, depending on another cause, might 
be termed with propriety nodosa pulpa, or granulated pulp, 
and may consist of one or more granules, round or irregular 
in shape. 
The former depending on wearing down of the tooth by 
mastication, and the latter depending on irritation from decay 
and other causes, is always confined to the limits of the pulp, 
and never adherent to the inner walls of the dentine. The 
former process may be considered as physiological, and the 
latter as pathological. One anticipated by nature, or the vis 
