1. W. C. Boyd , Vox Sanguines 8 , 1 ( 1963 ).
2. J. E. Cushing , N. L. Calaprice , G. Trump , Biol. Bull. 125 , 69 ( 1963 ).
3. R. T. Abbott American Seashells (Van Nostrand Princeton N.J.. 1964) p. 417.
4. The clams in this study were being used in the study of the haptenic properties of paralytic shellfish poison a potent toxin produced by the dinoflagellate Gonyaulax catenella and concentrated in certain bivalves that use Gonyaulax as a food source. The clams used were not contaminated with the toxin.
5. The clams were sent by Dr. A. K. Sparks University of Washington Seattle to Earl McFarren of the Robert A. Taft Sanitary Engineering Center. I obtained them from McFarren.