Three examples suggestive of non-genetic deformed beaks were found in the present experiments. One was found in an Osaka duck and two were found in chicken embryos.
The duck was hatched on the 28th day from an egg whose incubation was suspended for about three hours on the 25th day of incubation by interrpution of electric current. The duckling was raised for one year and the developmental condition of its deformed beak was observed. Its semen was also examined. The degree of the crooked beak became marked with time, but no abnormality was found in the general properties of the semen.
The other two were found in chick embryos. One was obtained from an egg whose incubation was suspended for about four hours on the 9th day of incubation by interruption of electric current. The shell was cracked on the 15th day of incubation.
The other was obtained from an egg whose incubation temperature was lowered six times a day for ten minutes for three days before the shell was cracked on the 10th day of incubation. The former showed the upper beak to be deformed and accompanied by unilateral anophthalmia, and the latter showed the upper beak to be deformed and accompanied by unilateral microphthalmia.
It is assumed that the deformity of the eye and beak may be induced by the same unfavourable environmental factor, but the factors and mechanism immediately involved in the non-heredetary abnormality are not known.