Comments: Scale Bar is 0.5 mm. About 50 times more
conodonts were recovered from this soft amorphous vein than were found in
the hard crystallized limestone surrounding it. This was the among
the largest of about 250 elements recovered in this sample. Picture
taken under oil immersion. Notice the "white matter" is coated
by a tough layer that is almost transparent. The cusp appears
to have been cracked late in development by lateral force, and then "healed
over" with asymmetrical enamel layers that gradually compensated for the
deviation. The enamel cracked at right angles to the lamina,
but the white matter cracked in a longitudinal fashion. Notice the
denticles on the left appear to have been "added on" with abnormal growth
over the outside of the element, suggesting the animal may have compensated
for the bent cusp. Side view X02 looks directly down on crack.
Views 04 and 05 give a closer look at the crack. 06, 07 and 08 give
high-magnification focus to the point where the small side of the crack penetrates
completely through the enamel lamina. Regrettably, this facinating
conodont was accidently crushed during study. The final view 09 shows
the appearance of a recent fracture. Fracture lines followed a similar
Z-shaped path through the lamina and white matter of the interior.
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