[Structure of the mammillary bodies of the hypothalamus of the bottlenosed dolphin].

In the bottlenosed dolphin (Tursiops truncatus) the hypothalamic corpus mammillaris has been studied using interperpendicular, sagittal, frontal and horizontal serial sections, impregnated in silver and stained with cresil-violet. Comparatively small dimentions of the corpora mammillaria in the bottlenosed dolphin are explained by presence of only two nuclei, medial and lateral. The lateral nucleus is nearly three times as large as the medial one. The size of the neurons in the medial nucleus is on the average two times as large as that of neurons in the lateral nucleus. The density of the neural cells distribution is a little greater in the lateral nucleus. The structure of the bottlenosed dolphin corpora mammillaria is compared with similar structures in other animals and the human being.