Demospongiae (Demospongea; phylum Porifera) A class of sponges which occur in both marine and freshwater environments. They have a leucon body structure. Both siliceous spicules and organic fibres may form a skeleton, but primitive types may lack skeletal support. This is the largest group of sponges and it first appeared in the Cambrian.
Demospongiae See DEMOSPONGEA.
More From encyclopedia.com
Glass Sponges , Hexactinellida (Hyalospongea; phylum Porifera) A group of sponges that first appeared in the Cambrian. They are of normal sponge shape and have skele… Polychaetes , Polychaeta (bristleworms; phylum Annelida) Class of annelid worms which possess distinct metameric segmentation. All have bristly parapodia (movable,… Gastrotricha , Gastrotricha (phylum Aschelminthes) A small class (or phylum in some classifications) of microscopic, pseudo-coelomate worms in which an excretory sy… Marine toad , Bufo marinus (marine toad, cane toad) See BUFONIDAE. marine toad (Bufo marinus) See BUFONIDAE. Calcareous Sponges , Calcarea (Calcispongea; phylum Porifera) A class of marine sponges that have a skeleton of calcareous spicules. Forms displaying leucon structure are… Hemichordata , Hemichordata (Stomochordata) A phylum first encountered in the Middle Cambrian Burgess Shale, British Columbia, Canada. The hemichordates are related…
About this article
All Sources -
Updated About encyclopedia.com content Print Topic
You Might Also Like