Influence of Sodium Thiocyanate on the Development of the Chick Embryo

Abstract

UNINCUBATED eggs were injected with 0.3–0.7 ml. of sodium thiocyanate of various concentrations (0.1 M, 0.5 M, 1 M) and incubated for 42–47 hours. The embryos thus developed showed a number of anomalies, first of all in the prosencephalon and partly in the mesencephalon; the metencephalon and myelencephalon being, in general, not so much affected. One of the most frequently observed anomalies of the latter was due to the abnormal closing of the neural tube: it seems that one of the neural folds was growing more quickly, thus being overlapped by the other (see section). This anomaly extended in various cases to the middle of the myelencephalon. Further changes were observed in the position of the heart, which was displaced, in extreme cases, into the precephalic region. No morpho-genetical changes of the somites were observed, though the number was lower (14–17) than that of normal embryos of the same age.