460 
PACIFIC SCIENCE, Vol. XX, October 1966 
for these, in addition to more obvious mecha- 
nisms, would be rewarding. 
SUMMARY 
1. The palatability of 48 species of marine 
invertebrates has been determined, of which 
24 species were found to be unpalatable to the 
four test species of fish. 
2. There is a significant difference in colour 
distribution between palatable and unpalatable 
tissues. 
3. Unpalatability remained when texture, 
colour pattern, and to some extent colour, were 
masked by presenting the tissue in a gelatin 
base. 
4. It is suggested that chemical defense 
mechanisms are widespread among inverte- 
brates, and an important factor in determining 
what fish eat. 
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