"A, Portion of the surface of a colony of Heliopora coerulea magnified, showing two calices and the surrounding coenenchymal tubes. B, Single zooid with the adjacent soft tissues as seen after removal of the skeleton by decalcification. Z1, the distal, and Z2, the proximal or intracalicular portion of the zooid; ec, ectoderm; ct, coenechymal tubes; sp, superficial network of solenia." — The Encyclopedia Britannica, 1910

Heliopora Corerulea

"A, Portion of the surface of a colony of Heliopora coerulea magnified, showing two calices and the…