The ultrastructural studies of Glioblastoma multiforme was carried out from tissue obtained from human intracranial neoplasms obtained in Madras Institute of Neurology.Light microscopy showed a highly cellular neoplasm with areas of sinusoidal necrosis palisaded by spongioblasts. The malignant cells exhibited hyperchromatism, pleomorphism, bizarre nuclei and there were marked endothelial proliferations. Mono nuclear cell aggregates are also seen.Ultrastructurally Glioblastoma multiforme exhibited great variation in size and shape of cells. In the main, the cells were off moderate size with ovoid nuclei and fine chromatin distributed evenly throughout the nucleus. Nucleoli were prominent and here also the two distinct nuclear membranes could be easily be made out. Fine pores were seen in the nuclear membranece.The cytoplasm was relatively lucent and showed various organelles such as mitochondria, Golgi apparatus and elements of the rought endoplasmic reticulum in moderate numbers. The endoplasmic reticulum was dilated in many regions and numerous electron dense bodies could also be seen.

Rhinosporidiosis is an unique fungal disease in that it has constantly eluded all efforts to culture the organism in vitro. Thus its exact life cycle is unknown, besides its various other biological characteristics. With this in view a study undertaken of the 54 cases showed the following L.M. and E.M. features.Light Microscopy: The fungi were seen to produce polypoid formations of fibrovascular connective tissue with a generally hyperplastic lining of squamous epithelium. The fungi themselves were in the form of multiple cysts of varying sizes and shapes. While most cysts appeared to be rounded or oval, tubular forms could also be seen. Sizes varied from 6-500 microns. The cyst wall appeared to have 2 layers, an inner cellulose and outer chitinous. The inner wall appeared associated with young spores and ovoid bodies 0.2 x 0.3 mm.