View source for Globigerinina

Planktonic in habit; test wall of perforate hyaline calcite, optically radiate, preferred crystal orientation with c-axis normal to surface; primary lamination bilamellar, secondary lamination due to addition of shell material during formation of new chamber; surface crust may develop at time of gametogenesis. M. Jurassic (Bathonian) to Holocene.


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''after Loeblich & Tappan (1988)''