Habib et al. (1973) recognized 2 morphologic classes for the glomerular changes seen in patients with mesangiocapillary (membranoproliferative) glomerulonephritis (MPGN). Type I is characterized by double contour appearance of the capillary walls due to mesangial cell interposition, with nonargyrophilic subendothelial deposits which are finely granular on electron microscopy. Type II is characterized by linear dense deposits within the basement membrane and only rare double contours. These 2 types appear to be distinct with no conversion of one type to another on serial biopsy. Strife et al. (1977) described a third variety in which there are not only subendothelial deposits but also numerous subepithelial and intramembranous deposits, associated with replication of the lamina densa and frequently disruption of the whole basement membrane.