ABSTRACT
A comparative study of the respiration of fishes from different ecological niches has shown that certain species are suited for the study of particular aspects of respiratory function because of their structure and physiological adaptations. In this context the study of the generally less active bottom-living forms has advantages where movements of the fish must be limited by the experimental arrangement. In the case of the dragonet, Callionymus lyra, there is the added advantage that water issuing from the opercular cavities can be readily collected into tubes fixed round the external openings without impairing the action of the opercular valves. These preparations proved of great value in making direct measurements of the ventilation volume under varying conditions (Hughes & Umezawa, 1968a). The relationship between ventilation volume and muscular activity was also studied very conveniently in this species (Hughes & Ballintijn, 1968).
