The endocrine cells of the stomach (proventriculus and gizzard) of the red-capped cardinal (Paroaria g. gularis) were studied by means of the transmission electron microscopy. In the proventriculus these cells are located among the secretory cells of the deep proventricular gland. In the gizzard they are located among the lining cells of the simple tubular gland. Both are elongated and have an oval nucleus, scarce elongated or oval mitochondria with little developing granular endoplasmic reticulum and numerous secretion granules