In 60 rhesus monkeys with experimental renovascular malignant arterial hypertension (25 one-kidney and 35 two-kidney model animals), we studied the so-called 'hard exudates' or white retinal deposits in detail (by ophthalmoscopy, and stereoscopic color fundus photography and fluorescein fundus angiography, on long-term follow-up). Some manifestation of hypertensive retinopathy developed in 19 one-kidney and 19 two-kidney animals, and white deposits formed in 14 and 5 monkeys, respectively. The onset of white deposits showed no correlation to severity of arterial hypertension or of retinopathy. All eyes with white deposits had antecedent macular or retinal edema. The deposits were everchanging, taking months or even more than a year to resolve. Our study suggests that in hypertensive retinopathy the white retinal deposits are most probably the result of exudative and/or neural degenerative processes. All the available pieces of evidence indicate that it is more appropriate to call the white deposits 'lipid deposits' than 'hard exudates'.