FREE AMINO ACIDS OF MARINE INVERTEBRATES 185 
Other chromatograms of extracts of tissues from Mollusca are shown in Figs. 35-37. 
In the bubble shell, Bullaria gouldiana (Fig. 35), the absence of the basic amino acids 
and the predominance of glutamic acid was notable. Also there is a strong unknown 
spot above taurine. Inthe periwinkle, Littorina planaxis (Fig. 36), the other dominant 
inhabitant of the high spray-zone niche, the concentrations of taurine, glycine, alanine 
and glutamic acid were found to be high. The periwinkle combats desiccation by 
sealing off the aperture of its shell with its operculum and with a mucoid secretion. The 
mussel, Mytilus californianus (Fig. 37), possesses both a high taurine and glycine 
content. 
Chromatograms of tissues from typical Echinodermata are shown in Figs. 38-41. 
In the sea urchin, Stvongylocentrotus purpuratus, the muscles of Aristotle’s Lantern 
had high levels of taurine and glycine (Fig. 38). The intestinal tract contained con- 
siderable tyrosine-O-sulfate (Fig. 39). The ripe gonads contained large amounts of 
glycine and the basic amino acids (Fig. 40). Glycine was the major constituent seen 
on the chromatograms of the free amino acids of the tube feet and associated muscles 
of the starfish, Pisaster ochraceus (Fig. 41). Also a considerable quantity of tyrosine- 
O-sulfate was detected. 
Studies also were made of some lower Chordata. The major constituents found on 
chromatograms of the red gland of the sea squirt, Czona intestinalis, were taurine, 
glycine and alanine (Fig. 42). A striking feature of the ripe female gonads from the 
same species was the large amount of histidine (Fig. 43). The final chromatogram is 
of an extract of the amphioxus, Branchiostoma californiense (Fig. 44). Even when 
the amount of extract was reduced to that corresponding to 25 mg of fresh tissue, 
the chromatogram was virtually swamped with glycine. 
We hope that this brief survey, in addition to providing a few aspects of free amino 

14 
Figs. 42-44. A sea squirt, Ciona intestinalis. Fig. 42, red gland; Fig. 43, female gonads. Amphioxus, 
Branchiostoma californiense. Fig. 44, extract equivalent to 25 mg tissue wt. Taurine, 5; alanine, 8; 
histidine, 11; glycine, 14. 
References p. 186 
