Aboral region (normal position).

Oral region.

Aboral surface (opposite to mouth).

Oral region with the lantern of Aristotle in formation.

Regression of larval tissues. Spicules of the larval skeleton are still present in the aboral region.

Oral region with the lantern of Aristotle in formation.

Lantern of Aristotle in the oral region.

Oral region.

Ambulacral feet and spines.

Aboral surface.

Regression of larval tissues. Spicules of the larval skeleton are still present in the aboral region.

Ossicles of the lantern of Aristotle in formation at the oral region.

Oral region.

Lantern of Aristotle in the oral region.

Podia and spine.

Ossicles of the lantern of Aristotle in formation at the oral region.

Lantern of Aristotle in the oral region.

Ossicles of the lantern of Aristotle in formation at the oral region.

Oral region with the lantern of Aristotle in formation.

Aboral surface.

Lantern of Aristotle.

Anus on the juvenile aboral surface (red curved structure).

Oral region.

Remnants of the larval skeleton in the aboral region of the juvenile.

Oral region with the lantern of Aristotle in formation.