Abstract:
The branching pattern of the Aa. carotes internae and the macroscopic blood supply to the hypophysis
and hypothalamus of the ostrich were studied on ten dissected acrylic vascular-injected heads and ten
corrosion preparations of acrylic vascular casts of the head. The A. carotis cerebralis was found to be
the only source of blood supply to the hypophysis and hypothalamus. The neurohypophysis was supplied
by the caudal hypophyseal and infundibular arteries. The pars distalis was supplied by portal vessels
from the ventral hypothalamic region,and it also received arterial blood directly from the infundibular
arteries. The hypothalamus received blood from the Aa. infundibulares, A. ventralis tecti mesencephali
and A. preopticae.