a1 Department of Physiology, University Medical School, Edinburgh, Scotland
a2 The Laboratory, Marine Biological Association, Citadel Hill, Plymouth
a3 Musée de Monaco, Monaco
Opportunities for measurements on living Nautilus are rare, and such studies as there have been on its locomotion tend to treat it as primitive compared with modern cephalopod molluscs. But the few measurements we were able to make on a healthy captive Nautilus living for several months in the Monaco Aquarium reveal considerable sophistication in the control of swimming - particularly in the way the funnel operates - and that the system possesses neuromuscular properties that may be fundamental to cephalopods as a whole. The use of the shell for transmitting the pressure pulse and for the in- and out-movements of the body during jetting are, however, peculiar to this member of the group.