ClipArt ETC
A diagram of an annulosa showing its external skeleton made up of segments or rings arranged along a longitudinal line, and consisting mostly of hardened skin. Labels: 1, vascular system,; 2, digestive organs; 3, ganglia.

Diagram of an Annulosa

A diagram of an annulosa showing its external skeleton made up of segments or rings arranged along a…

The Annulosa and Mollusca are furnished with a distinct alimentary canal that does not open into the body cavity. In most cases, the digestive canal communicates with the outer world by two-openings- a mouth and an excretory aperture. The annulosa system is demonstrated in the digestive apparatus of a beetle.

The Digestive Apparatus of a Beetle

The Annulosa and Mollusca are furnished with a distinct alimentary canal that does not open into the…