Abstract
Intranuclear cytoplasmic inclusions have been described previously in both human and animal tissue. So far as we are aware they are described in detail for the first time in this paper in 60 cases of malignant melanoma of the iris, usually in spindle cells. The light microscopic appearances are described, and electron microscopic studies of selected cases show clearly the genesis of these inclusions by cytoplasmic invagination of the nuclear membrane. Their significance is discussed. It is of interest that we have seen identical inclusions in malignant melanomas of the ciliary body, choroid, and conjunctiva but have not as yet reported our findings.