In the M₁ plants from seed irrdaiated Lactuceae, at least two types of chlorophyll mutant, “albo-xantha a” common to two cultivars of L. sativa, and “albo-xantha b” common to L. sativa and L. serriola, were recognised (c.f. von Wettstein et al. 1971, von Wettstein 1980). They are illustrated and discussed.