Quantification of crystal units in foraminiferal wall and the phylogenetic evaluation

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Three types of wall texture, microgranular, granular, and radial, have been known in the foraminifera. These textures are discriminated by the polarized features that showing the amoeba-shaped crystal units and their structure in the walls. The size of the crystal units is also significant for their discrimination. Based on these polarized features, some ideas applying the systematic criteria for foraminiferal taxonomy have been developed. Accepting this idea, however, externally similar forms distribute in different phylogenies. There have been problems for the application of the wall texture in the systematics.Apparently the optical features of walls are controlled by the wall thickness. Crystal units appear small for the thick-walled forms, whereas they appear large for the thin-walled ones. If the optical textures of walls are exactly controlled by their wall thickness, we have to clear this optical relationships. Thus I aimed to clear these features in different growth as well as different species with the microgranular and granular textures (as the types of jagged-granular and mosaic-granular). In order to analyze quantitatively the crystal units, automatic processing methods are introduced by using computer.I have understood that the optical features of wall textures are exactly determined by the wall thickness. Also there features are changed through their growth. I understand that wall thickness of foraminifera is basically controlled by their microhabitats including the life style. By using this relationship wall texture and wall thickness, we can evaluate their ecology. However, basic texture of walls is stable character for foraminiferal species.