Over 20 000 seeds of the Washington lupin (Lupinus polyphyllus Lindl.) were examined and measured in an experiment carried out over a 10 year period (1989±1999). Four dierent groups of Washington lupin seeds were found: dark, patterned, grey and light seeds. During the 10 year experiment, the total average number of seeds per plant decreased from 2654 (1990) to 1220 (1999), there was a slight decrease in seed weight per plant and an increase in the average weight per seed. There was a clear seed size/number trade-o at the intraspeci®c level. The relative proportions of each seed group also changed with patterned seeds becoming dominant (50 % at the beginning and 90 % at the end of the experiment), grey seeds remained constant (constituting 10 % of the total seeds) and the proportion of both dark (33 % at the beginning and 5 % at the end) and light (10 % at the beginning and 5 % at the end of the experiment) seeds decreased. Six hundred and sixty nine seeds were found to have a dierent testa ornamentation; they were distributed among the dierent groups as follows: 48 % patterned seeds, 29 % dark seeds, 12 % grey seeds and 11 % light seeds. There were no signi®cant dierences in the physical dimensions of the ornamented seeds compared with all other seeds. The results suggest that the Washington lupin is a mixture of dierent species and botanical forms; this is discussed in relation to possible selection pressures to produce both smaller and larger seeds. The possibility that changes in testa ornamentation are in¯uenced by genes controlling the synthesis of the seed coat pigment is discussed.

The mass spectral behaviour of nine l,fdioxolanes, seven 1,fdithiolanes and seven l,$oxathiolanes was studied under chemical ionization conditions with ammonia, isobutane, methane, acetone, acetone-d, or pentan-$one as reagent gas. The proton affinity of the first members in each series was not large enough for ammonia to protonate them; instead, the ionization took place through unstable [ M + NH,] + ions. Isobutane, which gave rise to abundant I M + HI+ ions in all cases, was the best reagent gas for the determination of the molecular mass. Methane chemical ionization caused extensive fragmentations either through ring cleavage or through the elimination of the largest substituent from ring positions 2 as a neutral hydrocarbon. The ketones used as reagent gas reacted to form adduct ions. In the case of dioxolanes and oxathiolanes, the [ M + R C O l + adduct ion decomposed through ring opening and then, as a consequence of intramolecular nucleophilic substitution, through the elimination of a neutral carbonyl compound. Resonance-stabilized dioxolanylium and oxathiolanylium ions were obtained for dioxolanes and oxathiolanes, respectively. This reaction was almost nonexistent for the dithiolanes.