3480. The numerous tentacular filaments surrounding the wide mouth resemble the shags of the chorion, which accumulate around the orifice of the umbilical cord to constitute a placenta in the higher animals.
The Corals are brood-eggs inclosed within the uterus of Nature or in the sea. The Coral-animals are an umbilical cord, treasured up for the embryo, while the Tubulariæ are only membranous vitelli, and the Gorgoniæ, ova with desiccated albumen.
3481. The families of Polyps stand therefore in the following order of significance:
Fam. 1. Infusorial Polyps—Tubulariæ.
2. Typical Polyps—Alcyoniæ.
3. Acalephan Polyps—Actiniæ.
Third Class.
Absorbent, Involucral Animals—Acalephæ.
3482. The Acalephæ also can only be brought under three divisions, viz. Röhrenquallen, or Physaliæ, Rippenquallen or Beroes, Hutquallen or Acalephæ.
3483. The Physaliæ are without doubt the lowest, being only giant Infusoria; the Beroes are allied through their simple bodily cavity, to the Gorgoniæ; the Acalephæ, through their form, to the Madrepores, especially the Actiniæ.
3484. They range therefore in the following order of significance:
Fam. 1. Infusorial Acalephæ—Physaliæ.
2. Polypary Acalephæ—Beroes.
3. Typical Acalephæ—Acalephæ.