"Single zooid with the adjacent soft tissues as seen after removal of the exoskeleton by decalcification. Z1, the distal, and Z2, the proximal of intracalicular portion of the zooid; ec, ectoderm; ct, coenenchymal tubes; sp, superficial network of solenia." —Encyclopedia Britannica, 1910

Zooid

"Single zooid with the adjacent soft tissues as seen after removal of the exoskeleton by decalcification.…