Treatment of Triticum plants with 2,4-D profoundly affects inflorescence morphogenesis and results in the production of various abnormalities, amongst which are branched heads, whorls of spikelets. superimposed pairs of spikelets (‘banana’ twin spikelets) and paired spikelets borne at the same level (‘yoked’ spikets). Often more than one kind of abnormality is observed in a single head. Except for ‘banana’ twin spikelets, none of the induced abnormalities are duplicated by abnormalities which occur spontaneously in untreated plants. Disturbance due to treatment is only temporary and later the terminal region of the apex recommences growth along a normal pattern of morphogenesis.