The study of the micromorphological features of the vasculature of the lung of the dromedary camel during the prenatal and mature stages of life revealed the following: I- Prenatal stage: The pulmonary artery takes the muscular form during the early foetal ages 8 cm, 9.5 cm and 19 cm, however, it becomes elastic at the 39.5 cm, 51 cm, 53 cm and full term ages. II- Mature stage: 1- The pulmonary arteries are of the elastic type. Their wall is relatively thin in comparison to their diameter. Vasa vasora of the glomus bolster type are recorded within the wall of the pulmonary artery. 2- The pulmonary veins have a smooth muscular media down to a diameter of 100 - 120 microns. At a vessel diameter of 164.14 -658.94 microns the lumen of the pulmonary veins shows intermittent constrictions resulting from the corresponding muscular pad-like protrusions from the media. 3-The presence of a rich vascular bed in the fringe-like extensions is probably an accommodation for regulation of body temperature through radiation of heat from from the blood contained in these vessels.
