2. Mustard gas treatment.

At California Institute of Technology tassels beginning to shed pollen were placed in mustard gas solution for 18 hours, at the end of this time and after 40 hours the pollinations were made. Ears from the pollen from treated tassels showed a higher frequency of small kernels, the highest being from the pollen obtained at the end of 40 hours.

C. H. Li and

C. R. Burnham

Of 589 plants grown from the crosses using pollen from treated tassels, two with 75 per cent pollen abortion, one with 65, three with 50 and one with 20 per cent were observed. These also had aborted ovules. Self‑pollinated plants with normal pollen have been tested; two segregated albino seedlings. No partially sterile plants or segregation for new characters were observed in the checks.

M. A. Ibrahim,

D. M. Gopinath and

C. R. Burnham

Further trials using longer treatment periods and stronger solutions were started last sumer by M. A. Ibrahim.