Fine Structure of Annulate Lamellae

Annulate lamellae represent a poorly understood class of cytomembranes (see references 14-18). The structural resemblance and proximity (in some cases) between the nuclear envelope and annulate lamellae have led to the concept that the annulate lamellae represent a product of the nuclear envelope although the methods propoundedly involved in the morphogenesis of annulate lamellae are indeed varied (14-17, 21, 30, 34). In almost all cases, the pores of the annulate lamellae have associated with them a dense material of variable nature. The high density associated with this region has prevented characterization of much structural detail in this area. It is the purpose of this report to describe the structural components responsible for this density in the annulate lamellae of certain germ cells.