Corneas of tadpole, mouse, rat, guinea pig, rabbit, cat, cattle, and human were examined by TEM and SEM in a comparative study. The differences between species were noted mainly by using TEM. Bowman's layer showed a tendency to be well developed in higher mammals. Tadpoles lack a Bowman's layer, lower mammals have a thin Bowman's layer, and higher mammals have a thick Bowman's layer. The boundary between the substantia propria and Descemet's membrane was distinct in higher mammals. On the other hand, there are no differences in thickness of the collagen fibrils that constitute Bowman's layer and those of the substantia propria. NaOH digestion was utilized for SEM preparation. SEM imaging revealed a textured appearance of the epithelial side of Bowman's layer. In Descemet's membrane, fibrous long spacing (FLS) fiber-like structures, which are arranged in parallel to the endothelium, were observed by both TEM and SEM. To our knowledge, this is the first report of SEM observations of FLS fiber-like structures on the endothelial surface of Descemet's membrane. SEM at a plane normal to the plane of the cornea showed that Descemet's membrane has a piled laminar structure. Descemet's membrane is closely associated with the collagen layer of the substantia propria. Collagen fibrils invading from the substantia propria into Descemet's membrane were observed with both TEM and SEM.

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Daily electrical stimulation of the amygdala in Senegalese baboons (Papio papio) resulted in the development of generalized convulsive seizures focal onset through five distinct clinical stages in an average of 72 days. The chronologic pattern of electroclinical features suggested that vertical intrahemispheric ictal dissemination was of primary importance in the progressive seizure development. Some animals developed spontaneous recurrence of both partial complex and primary generalized seizures. The kindling preparation in P. papio represents a unique model of human epilepsy with its secondary generalized convulsive seizure development, spontaneously recurrent partial and primary generalized seizures in the background of predisposed epileptogenic susceptibility.

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