304 Papers from tlic Marine Biological Laboratory at Tortugas. 



athcrina and cassiopea, made by shaping the cassiopea to the form of an 

 atherina body and sewing to this the head and tail of an atherina. The 

 whole was blue and at a little distance hardly to be distinguished from an 

 atherina. It was at once taken. 



The next day (July 15) after a previous feeding of but 18 uncolored 

 atherinas, 2 pieces of the rim of cassiopea were stained blue and thrown to 

 the snappers after a single blue atherina. The pieces of cassiopea were 

 about I inch wide and 3 inches long. One continued to pulsate ; the other 

 did not. Both were at once taken. 



Experiment j-/; Shortly afterward pieces of the arms of cassiopea were 

 trimmed as near as possible to the size and form of atherina. They were 



Table 14. — Behavior of the laboratory colony of gray snappers toicard blue and red 

 atherinas and toivard blue and red atherina-shaped cassiopea arms, when offered, 

 in alternation after normal atherinas. 



tna = normaI atherina; i>a=blue atherina; ra = red atherina; ftir=blue cassiopea; rc = red cassiopea.] 



