Fig. 2. gram mutations affect growth and asymmetry of petals. (A-D) A wild-type flower. (A) A lateral (left) and dorsal (right) view. (B) Two rows of dense yellow hairs (^*), are present on the adaxial surface at the junction between the ventral and lateral petals within the corolla tube. (C) In a section, taken at the position of the bar in B, the junction between petals is flanked by veins in which xylem elements (x) are adaxial to phloem (p; D). (E-H) gram mutant flower. (E) Mutant flowers are smaller than wild-type ones and the dorsal petals are free laterally and more symmetrical in shape. (F) The junction between ventral and lateral petals (arrowhead in F) is flanked by ridges containing enlarged abaxialised veins (G, and enlarged in H) that have central xylem elements (x) surrounded by phloem (p). Epidermal tissue between the ridges (arrowhead in G) has abaxial identity, as evidenced by a higher level of anthocyanin pigmentation characteristic of abaxial petal epidermis and absence of yellow hairs.