differentiation of crystal-containing cells during anther development and crystal types in the anther of petunia hybrid grandiflora (solanaceae)*

calcium crystals are evident in many parts of anther. there is little literature about differentiationof crystal-containing cells and crystal formation during anther development. petunia hybrid grandifloraflower buds collected at different developmental stages were fixed and studied. the results revealed thatyoung anthers are tetrasporangiate and in each of the four corners, the primary parietal layer externally andprimary sporogenous cells internally, arise from periclinal divisions of the archeosporial cells. in the younganther, septum and connective cells contain calcium crystals as druse. at stomium, there is an arrangement ofa band of 8-14 cells just beneath the epidermis which densely stain and lack visible vacuoles. during thedivision of sporogenous cells and the formation of crescent shaped tissue, no crystals are seen in hypodermalcells. in this stage, druse crystals become larger in connective tissue. while meiosis is occurring, thehypodermal cells of stomium are elongated, yet crystals are not observable. during pollen development,hypodermal cells degenerate and sand crystals appear. it seems that these crystals result from druse crystal.