Developmental studies do not confirm the general opinion that the androecium or the gynoecium is spiral in Sagittaria latifolia. After the inception of three sepal primordia, three bulges (petal–stamen primordia) are formed on radii alternating with the sepal primordia. On each petal–stamen primordium a petal is initiated and subsequently a pair of stamens in the male floral bud and staminodia in the female floral bud. Next, two antesepalous primordia are formed between the first paired primordia. Further stamens (or staminodia and carpels in the female floral bud) are formed centripetally, more or less alternating with the previous ones at subsequently higher levels.