1. C14-labeled ß-aminopropionitrile distributed throughout the egg contents within 10 minutes postinjection. By ion exchange chromatography and electrophoretic analysis three major components of the extractable dialyzable radioactive material could be demonstrated, representing at least 80 per cent of the total. The acidic and basic components were identified as ß-aminopropionitrile and cyanoacetic acid, while the fraction isoelectric at pH 5.3, consisting of two components, remained unidentified.
2. Less than 1 molecule of ßAPN per 100 molecules of protein was present in the highly purified extractable lathyritic bone collagen indicating that binding of the lathyrogen is not a factor in collagen extractability.
3. The proximity of ßAPN to collagen in bone is not essential to its extractability.
4. The effect of incubation temperature of the embryo on collagen extractability suggests the involvement of a metabolic process in this phenomenon.