ULTRASTRUCTURE OF THE TUBOID GRAPTOLITE TUBOTHECA

Adam Urbanek  and  Piotr Mierzejewski

Paläontologische Zeitschrift 1982, 56, 1/2, 87-93
PORTAL OF GRAPTOLITES AND PTEROBRANCHS SPONSORED BY "M.M. PLUS M." SZTANDARY >>
The wall of the tubotheca of the tuboid graptolite
Epigraptus eisenacki Mierzejewski has been studied
with TEM. It was found that the tubothecal wall is
composed of the cortical tissue which differs only
slightly from the same tissue described in Dendroidea
and
Mastigograptus sp. In addition a giant tubotheca in
Discograptus schmidti Wiman has been examined with
SEM. The tubothecae studied seem to confirm a
non-graptolite nature of the organism living in them,
while providing evidence that the tubotheca wall was a
genuine graptolite structure overgrowing these
organisms.

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Tubotheca of Epigraptus eisenacki Mierzejewski:
Transverse section of the wall; p - pseudofusellar
intercalations.