Open AccessCarterina: its morphology, structure and taxonomic position
Author(s) -
Helle Ploug Hansen,
H. Grønlund
Publication year - 1977
Publication title -
bulletin of the geological society of denmark
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.674
H-Index - 28
eISSN - 2245-7070
pISSN - 0011-6297
DOI - 10.37570/bgsd-1977-26-11
Subject(s) - sponge spicule , layering , morphology (biology) , position (finance) , concentric , shell (structure) , geology , geometry , biology , materials science , paleontology , botany , mathematics , composite material , finance , economics
The external and internal morphology of Carterina spiculotesta is described and illustrated. Sections and decalcified preparations demonstrate that the spicules composing the wall have a concentric layering. There is, moreover, a 0.1-0.2 µm sub-layering at right angles to the long axis of the spicules. The inner organic chamber lining is different from the organic matrix in being laminated and more compact. There are no pores in the shell. It is concluded that the spicules most likely are secreted by the animal. It is suggested that Carterina should be transferred to the Textulariina and that the 'allochthonous' spicules ('allochthonous' relative to their final position in the wall) must be regarded as distinct from the 'autochthonous' material in the walls of Miliolina and Rotaliina.