1. Butenandt, A., Schramm, G., and Kudsus, H., Ann., 531, 176 (1937); Inhoffen, H. H., Angew. Chem., 59, 207 (1947) and references cited therein.
2. Cf. Inhoffen, H. H. (ref. 1). Fiat Report No. 996 (London: H.M. Stationery Office, 1947). Djerassi, C., and Scholz, C. R., J. Amer. Chem. Soc., 71, 3962 (1949); Wilds, A. L., and Djerassi, C., ibid., 68, 2125 (1946). Hershberg, Rubin and Schwenk, J. Org. Chem. (in the press).
3. Pearlman, W. H., and Wintersteiner, O., J. Biol. Chem., 132, 605 (1940).
4. Pearlman, W. H., and Wintersteiner, O. (see following letter).
5. Barton, D. H. R., and Rosenfelder, W. J., Nature, 164, 316 (1949). Wintersteiner, O., and Moore, M., ibid., 164, 317 (1949).