The phylum of sponges which are sessile, suspension-feeding, multicellular animals that utilize flagellated cells called choanocytes to circulate water. Most are hermaphroditic. They are probably an early evolutionary side branch that gave rise to no other group of animals. Except for about 150 freshwater species, sponges are marine animals. They are a source of ALKALOIDS; STEROLS; and other complex molecules useful in medicine and biological research.
    

concept

Cartilage, trabecular bone and bone marrow in a mouse femur

An elderly anatomist contemplates the heart that he has excised from the corpse of a beautiful, young woman. Photogravure by R. Schuster, 1907, after a painting by E. Simonet, 1890.

Blood vessel in a melanoma, SEM

Canine skull with osteosarcoma

An elderly anatomist contemplates the heart that he has excised from the corpse of a beautiful, young woman. Photogravure by R. Schuster, 1906, after a painting by E. Simonet, 1890.

Cocoon from medicinal leech Hirudo verbena

La maladie des pêcheurs d'éponges nus / Skévos Zervos.

Orchid aerial root (Phalaenopsis sp.), transverse section

A bibliography of Protozoa, sponges, Coelenterata, and worms : including also the Polyzoa, Brachiopoda, and Tunicata, for the years 1861-1883 / by D'Arcy W. Thompson ; edited for the syndics of the University press.

The Fauna of British India, including Ceylon and Burma / edited by A.E. Shipley. Freshwater sponges, Hydroids & Polyzoa / by N. Annandale.

Sponges

Images

Catalogue

Cocoon from medicinal leech Hirudo verbena

La maladie des pêcheurs d'éponges nus / Skévos Zervos.

Orchid aerial root (Phalaenopsis sp.), transverse section

A bibliography of Protozoa, sponges, Coelenterata, and worms : including also the Polyzoa, Brachiopoda, and Tunicata, for the years 1861-1883 / by D'Arcy W. Thompson ; edited for the syndics of the University press.

The Fauna of British India, including Ceylon and Burma / edited by A.E. Shipley. Freshwater sponges, Hydroids & Polyzoa / by N. Annandale.