1. Towe, K. M., Biomineral. Res. Repts., 4, 1 (1972).
2. Wilbur, K. M., in Physiology of Molluscs I (edit. by Wilbur, K. M., and Yonge, C. M.), 243 (Academic Press, London, 1964); Wilbur, K. M. in Chemical Zoology, VII Mollusca (edit. by Florkin, M., and Scheer, B. T.), 103 (Academic Press, London, 1972).
3. Bevelander, G., and Nakahara, H., Calc. Tiss. Res., 3, 84 (1969); 7, 31 (1971).
4. Erben, H. K., Biomineral Res. Repts., 4, 15 (1972); 7, (1974).
5. Spurr, A. R., J. ultrastr. Res., 26, 31 (1969).