"Tangential section of a larva of Astroides calicularis which has fixed itself on a piece of cork. ec,…
"Gelatinous substance of the disc of Aurelia, showing-a, fibrous trabeculae, and b, wandering endoderm…
"Portion of the body-wall of Hydra, showing ectoderm cells above, separated by "structureless lamelia"…
"Diagram of a Diblastula. a, orifice of invagination (blastopore); b, archenteric cavity; c, endoderm;…
"Formation of the Diblastula of Eucope (one of the Calyptoblastic Hydromedusae) by delamination. A,…
"Vacnolated endoderm cells of eartilaginous consistence from the axis of the tentacle of a Medusa (Cunina)."…
"Diagram of a typical Hydrozoan polyp. EC., Ectoderm; EN., endoderm; C., the cavity of the gut (coelenteron);…
"Diagram showing possible modifications of persons of a gymnoblastic Hydromedusa. a, hydrocaulus (stem);…
"Diagram showing possible modifications of the persons of a Calyptoblastic Hydromedusa. a, hydrocaulus…
"Portions of sections through the disc of medusae. The upper one of Lizzia, the lower of Aurelia. el,…
"Simple tentaculocyst of one of the Trachomedusae (Rhopalonema velatum). The process carrying the otolith…