ClipArt ETC
"Diagrammatic vertical section through disc and base of one of the arms of Antedon rosacea. The section is inter-radial on the left, radial on the right. t., Ciliated openings in body wall; h., sub-epithelial ambulacral nerve; l., water-vascular canal; k., tentacle; r., mouth; s., intestine; g., central plexus, with "chambered organ" at its base; f., coelom; R1.-R3., radial plates; Br., brachial plates; u., muscle; a., axial nerve-cord; d., central capsule; C.D., centro-dorsal plate; p., cirri; e., nerve branches from central capsule to cirri." -Thomson, 1916

A. Rosacea Arm

"Diagrammatic vertical section through disc and base of one of the arms of Antedon rosacea. The section…