178 J. S. KITTREDGE et al. 
evolution of similar metabolic characteristics is not at all uncommon?!. Often there was 
found to be a greater difference between the free amino acid patterns of the various 
tissues of a given species than between the same tissue of related species?. An example 
of this was the cbservation of a marked similarity of the free amino acid patterns of 
the radular muscles throughout a number of the Gastropoda (snails). An exception 
to the lack of distinctive phylogenetic patterns is the occasional occurrence of a 
specific compound. Where the ability to synthesize a new compound occurred early 
in the evolution of a major group, this capacity may be maintained throughout its 
evolution and morphological diversification. 
At present we are examining two new amino acids occuring in the Coelenterata. A 
point of taxonomic interest is the marked difference in the concentration of these two 
new compounds, relative to the other free amino acids, in the two closely related sea 

, 
13 


Figs. 5-10. Fig. 5, the sea pansy, Renilla kollikevi; Fig. 6, a Bryozoan, Chilostomata sp; Fig. 7, sea 
anemones, Anthopleura elegantissima; Fig. 8, A. elegantissima, hydrolyzed extract; Fig. 9, Metri- 
dium senile; Fig. 10, Corynactis californica. Leucines, 3; valine, 4; taurine, 5; alanine, 8; glutamine, 
13; glutamic acid, 17; unknown amino acids, X and Y. 
i, ie, 
Refevences p. 186 
