[Development of the lens and zonulae in the human embryo]

The embryonic development and ultrastructures of the lens and zonulae in 212 eyes of 131 human embryos were studied by light and electronic microscopy, with the finding that the capsule and zonulae appeared earlier than previously reported. The laminate structure of the capsule was observed in the 7 week embryo, and the early structures of zonulae were discernible in the 10th week on the basement membrane of the non-pigmental epithelium of the ciliary body and on the capsule, indicating that the capsule was specialized basement membrane of the lenticular epithelial cells, and the zonulae originated from the non-pigmental epithelium of the ciliary body and the capsule of lens.