This illustration shows the calcareous shell Chrysalidina gradata. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Chrysalidina Gradata

This illustration shows the calcareous shell Chrysalidina gradata. These shells are mostly very small,…

This illustration shows the calcareous shell Cuneolina pavonia. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Cuneolina Pavonia

This illustration shows the calcareous shell Cuneolina pavonia. These shells are mostly very small,…

This illustration shows the calcareous shell Flabellina rugosa. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Flabellina rugosa

This illustration shows the calcareous shell Flabellina rugosa. These shells are mostly very small,…

This illustration shows the calcareous shell Frondicularia Annularis. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Frondicularia Annularis

This illustration shows the calcareous shell Frondicularia Annularis. These shells are mostly very small,…

This illustration shows the calcareous shell Fusulina cylindrica. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Fusulina Cylindrica

This illustration shows the calcareous shell Fusulina cylindrica. These shells are mostly very small,…

This illustration shows the calcareous shell Fusulina cylindrica. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Fusulina Cylindrica

This illustration shows the calcareous shell Fusulina cylindrica. These shells are mostly very small,…

This illustration shows the calcareous shell Globigerina rubra. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Globigerina Rubra

This illustration shows the calcareous shell Globigerina rubra. These shells are mostly very small,…

This illustration shows the calcareous shell Grammostomum phyllodes. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Grammostomum Phyllodes

This illustration shows the calcareous shell Grammostomum phyllodes. These shells are mostly very small,…

This illustration shows the calcareous shell Lituola nautiloides. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Lituola Nautiloides

This illustration shows the calcareous shell Lituola nautiloides. These shells are mostly very small,…

"Portion of the calcareous corallum of Millepora nodosa, showing the cyclical arrangement of the pores occupied by the "persons" or hydranths." — Encyclopedia Britannica, 1893

Millepora Nodosa

"Portion of the calcareous corallum of Millepora nodosa, showing the cyclical arrangement of the pores…

This illustration shows the calcareous shell Nodosaria vulgaris. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Nodosaria Vulgaris

This illustration shows the calcareous shell Nodosaria vulgaris. These shells are mostly very small,…

This illustration shows the calcareous shell Nummulites nummularia. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Nummulites Nummularia

This illustration shows the calcareous shell Nummulites nummularia. These shells are mostly very small,…

This illustration shows the calcareous shell Rotalia globulosa. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Rotalia Globulosa

This illustration shows the calcareous shell Rotalia globulosa. These shells are mostly very small,…

This illustration shows the calcareous shell Textilaria globulosa. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Textilaria Globulosa

This illustration shows the calcareous shell Textilaria globulosa. These shells are mostly very small,…

This illustration shows the calcareous shell Triloculina Josephina. These shells are mostly very small, and yet through their abundance they have been very important in limestone-making.

Triloculina Josephina

This illustration shows the calcareous shell Triloculina Josephina. These shells are mostly very small,…