Text Fig. 1 (Left): Diagrammatic representation of the column ectoderm as seen in a transverse section stained by the Mallory/Azan technique.

Scale measures 20μ.

a, type A gland cells; b, type B gland cells; c, type C gland cells; e, supporting cell; m, mesogloea; n, nucleus; p, projection; s, nerve cell.

Text Fig. 2 (Right): Nematocysts found in the column ectoderm in I. olivacea.

Scale measures 10μ.

a, atrichous anisorhiza; b, microbasic amastigophore; c, holotrichous isorhiza; d, capsule; e, butt; 1, lid; t, tube.