Anatomy & Physiology

The basic body plan of cephalopods is remarkably homogeneous. It is divided into three basic regions, the head, the foot (highly modified into flexible appendages) and the visceral mass enclosed by the mantle. The external shell which is a feature of the hypothesised molluscan ancestor of modern cephalopods has been internalised, and transformed into a buoyancy compensation device, or completely lost in most extant members of this group. The most complex central nervous system (CNS) of any invertebrate is found in cephalopods and they have highly developed sensory systems which supply it with information (Ruppert et al. 2004).

Please see the tabs for more information on the anatomy and physiology of cephalopds in general and I. notoides in particular.

Preserved specimen of I. notoides with the three major body regions and scale bar shown. Photograph by Samantha Reynolds.