Ocular onchocerchiasis occurs in the Belgian Congo and is remarkably frequent in a great number of widespread areas. It is possible that American onchocerchiasis originated in Africa; it seems also probable that human onchocerchiasis is an animal onchocerchiasis adapted to man, such as for instance Onchocerca Gibsoni. It is important for a practitioner to be able to recognize the manifestations of onchocerchiasis. They show particular characteristics, which we shall presently discuss and which can be better understood by the aid of coloured iconography. In order to have a clear understanding of the drawings presented, we think it necessary to refer to them in detail. But we shall first mention a few signs, which considered together are characteristic of the ocular complications of onchocerchiasis. I beg to claim the reader's indulgence for deficiency in regard to drawing technique. However, it is necessary to show in this way the lesions observed since I lack the special complicated apparatus required for photographic reproduction.