AFTER TESTS BY 
SEA BIOLOGIS TS 
By the Associated Presi * 
Shiimp with heads of 
pastel colors may be turning 
up in the catches of shrimp 
trawlers next year. 
The Pish and Wildlife 
Service said today biologists 
of the Institute of Marine 
Science of t^ University of 
Texas have discovered a safe 
and simple way of identify- 
ing shrimp for study through 
use of dyes. 
The dyes are introduced 
into a shrimp's body by 
hypodermic needle or 
through^ food. They color 
only the head of the shrimp. 
So far blue and red dyes 
have been used successfully. 
Some shrimp have shown 
the coloring for as long as 
215 days and through two 
molts of their shells. 
