Editing Archaeocyatha (section)

==Morphology==
[[Image:Archaeocyatha.png|thumb|300px|'''1'''&nbsp;– Gap (''intervallum'')
'''2'''&nbsp;– Central cavity
'''3'''&nbsp;– Internal wall
'''4'''&nbsp;– Pore (all the walls and septa have pores, not all are represented)
'''5'''&nbsp;– Septum
'''6'''&nbsp;– External wall
'''7'''&nbsp;– Rhizoid|left]]The typical archaeocyathid resembled a hollow [[horn coral]]. Each had a conical or vase-shaped porous [[skeleton]] of [[calcite]] similar to that of a [[sea sponge|sponge]]. The structure appeared like a pair of perforated, nested ice cream cones. Their skeletons consisted of either a single porous wall (Monocyathida), or more commonly as two concentric porous walls, an inner and outer wall separated by a space. Inside the inner wall was a cavity (like the inside of an [[Ice cream cone|ice cream cup]]). At the base, these pleosponges were held to the [[Substrate (marine biology)|substrate]] by a [[holdfast (biology)|holdfast]]. The body presumably occupied the space between the inner and outer shells (the intervallum).