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(A) Four vegetative leaflets (control), (B) Two long and broad leaflets (0.50% caffeine), (C) A very small curved leaflet (0.25% caffeine), (D) Broad obcordate (heart-shaped leaflet) [15 ppm Pb(NO3)2], (E) Unequal leaflets; two large, broad and another two small [20 ppm Pb(NO3)2], (F) Thick, small and light green leaflets (1.0% caffeine). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)
