142 American Fisheries Society 



taste it and at the same time feel it. The sense of taste 

 then probably tells them whether it is edible while the 

 sense of touch enables them to locate it so accurately that 

 they turn and seize it without seeing it. For fish that do 

 not make much use of the eyes in feeding it is well then 

 if the bait has both taste and odor. As a practical meas- 

 ure it is perhaps well when seeking such fish to avoid 

 baits that seem to us merely salt, sour or bitter and 

 without odor and to use those that have odor or that 

 seem to have other qualities of taste than salt, sour or 

 bitter. To use a sweetened bait would be unavailing in 

 any case. 



C. The Senses op Mass-Movement, Hearing and 

 Sight. The senses of fishes that take note of vibrations 

 (not emanations) , are hearing, vision and another sense 

 not possessed by man. This other sense deals with mass 

 movements in the water either currents (constant move- 

 ments in one direction), or very slow vibrations ► back 

 and forth movements). Hearing is concerned with the 

 more rapid vibrations of the water that are perceived 

 as sounds, while sight is concerned of course with the 

 light waves that traverse the water. The organs of these 

 senses may be said to be distance receptors sensitive to 

 movements, but not to chemical substances. 



1. The Sense of Mass Movement. 



Along the middle of each side of the body in most fishes 

 is a peculiar row of scales, those of the lateral line. In 

 each of these is a small opening which leads into a short 

 tube. These tubes terminate in a larger, tunnel-like tube 

 beneath the skin, the so-called lateral-line canal, which 

 runs along the side of the body. This canal extends also 

 on to the head, where it divides into three main branches 

 and communicates with the surface by numerous short 

 tubes, whose openings are easily seen with the naked 

 eye. Within the lateral line canal on head and body are 

 numerous small sense organs, the lateral-line organs. 

 From these nerves extend to the brain. The use of these 



