Cereus opening

Do you know the night-blooming cereus?  It is a flower most strange and magical. It blooms for a few hours, only at night. By morning it’s wilted.  It has a mild, almost-lemony fragrance and, when completely opened, it is the size of a human hand with fingers spread wide. The bud starts from the side of a leaf that looks like a succulent. The size of the stem and blossom when mature, dwarf the leaf and the leaf’s stem. This image is the beginning of the opening, which usually takes about a half hour. More cereus images to come.