LOBSTER OE CEATFISH 169 



branchia move with it? Do you think the po- 

 dobranchise are moved when the animal walks ? 

 Can you discover that the epipodites have any 

 function ? 



d. I^ervous properties. 



1. Touch. — With a long bristle gently touch the 



animal in the following places, noticing each 

 time whether or not, by moving or otherwise, 

 it gives evidence of feeling the touch : The 

 dorsal surface of the carapace, the dorsal sur- 

 face of the various abdominal segments, the 

 telson, the lower edge of the branchiostegite, 

 the hairs on the various appendages of the 

 thorax, any of the mouth parts within reach, 

 various points from the tip to the base of the 

 antennae, likewise of the antennules, the stalk 

 and the surface of the eye, and the rostrum. 

 Is the sense of touch distributed over the 

 entire surface of the body ? Are there any 

 appendages which are especially sensitive to 

 touch ? If so, can you give any reasons for 

 this ? Do the hairs on various parts of the 

 body show different degrees of sensibility to 

 touch? Are any of them so sensitive as to 

 warrant regarding them as " tactile hairs " ? If 

 so, where are they and why should they be so 

 situated ? 



2. Taste. — Put a piece of bread and a piece of meat 



in the water near the animal. Does it show 

 any preference for either of these ? Try a piece 

 of fresh and a piece of decaying meat. "Which 

 does the animal prefer ? 



3. Smell. — Lay a piece of meat in the bottom of a 



