spirula

A small squid of the genus Spirula, having a spirally coiled, chambered, internal shell often found on beaches.

In Cephalopoda: A genus of sepioid cuttlefishes, typical of the family Spirulidaæ, having a delicate shell in the hinder part of the body rolled into a flat or discoidal spiral, with discrete whorls whose involute spire presents ventrally, and no guard.

A member of this genus.

In sponges, an irregular spineless polyact spicule of spiral form.

A genus of cephalopods having a multilocular, internal, siphunculated shell in the form of a flat spiral, the coils of which are not in contact.

Any of the cephalopod genus Spirula

a small tropical cephalopod of the genus Spirula having prominent eyes and short arms and a many-chambered shell coiled in a flat spiral