Publication Date:
2015-09-09
Description:
The formation of skeletons is one of the most conspicuous characteristics of Scleroactinian
corals. Naturally, many scholars have worked on this problem using either
classical histological methods, such as Fowler (2), Boume (1), Krempf (11), Hayashi
(4), or modem methods of electron microscope or of isotopes, such as Wainwright (13),
Sato (12), and Goreau (3).
In our electron microscopic studies on the Scleroactinian corals we also examined
both polyps and skeletons from various kinds of corals. However, the skeleton is too
hard to get good results for the elucidation of the skeleton formation. This fact is more
pronounced when we use materials from the coasts of the main islands of Japan where
the corals grow very slowly. The processes of spicule formation in a Gorgonian coral
(5) and Alcyonarian corals (Heteroxenia (9) and organ-pipe coral (10)) are observed
within scleroblasts which usually originate in the ectodermal cells and are embedded in
the mesogloea.
In some rapidly growing corals. calicoblastic cells are found around the growing
portion of the skeleton, but seldom in the old or resting portion. This fact suggests
that the skeleton is formed by calicoblastic cells which are derived from the ectodermal
cells and which accumulate calcareous substances within them, thus turning into a
skeleton.
Type:
Article
,
NonPeerReviewed
Format:
text