Two remaining vessels (6 and 8) are often found as branches from the coracoid artery. They were small and often were collapsed in the individuals I dissected, but were most clearly seen in _Iridoprocne bicolor_. The vessels occasionally had a common base, and in some specimens only one vessel was found. The first artery (6) passes mediad into _M. sternocoracoideus_, or continues across that muscle onto the inner face of the sternum. The second vessel (8) also supplies _M. sternocoracoideus_ or the inner surface of the sternum, and often a large branch continues across the dorsal surface of the coracoid to _M. coracobrachialis posterior_. Fig. 3 shows a composite of these vessels; not all branches were seen in any one specimen. In the specimen of _I. bicolor_ a foramen existed on the lateral edge of the coracoid where the branch (of 8) to _M. coracobrachialis posterior_ passed. An examination of skeletons of five to 10 individuals each of the five species for which dissections were made, and of _Petrochelidon pyrrhonota_ (Cliff Swallow) and _Tachycineta thalassina_ (Violet-green Swallow), in the University of Kansas collection, showed that most coracoids of these seven species of swallows had a small notch (as shown in Fig. 4) or a complete foramen there. The thoracic artery (3) arises from the subclavian opposite the base of the coracoid artery, or from the base of the coracoid artery. Of the five specimens of _P. subis_ dissected, one individual had the former arrangement on both sides, and one had the latter on both sides, whereas in the remaining three the thoracic artery arose from the coracoid artery on one side and from the subclavian on the other side. The distance between these two possible sites of origin is slight. The thoracic artery usually passes ventral to _M. costi-sternalis anterior_. Occasionally a small artery (13) could be traced from the main trunk of the thoracic artery to that muscle. The main thoracic artery bifurcates near the insertion of _M. costi-sternalis_, the branches traveling posteriad on both sides of the muscle. On one side of one specimen this artery bifurcated immediately after leaving the subclavian, the dorsal trunk passing dorsal to _M. costi-sternalis anterior_, and the ventral trunk ventral to the muscle. On the other side of the same individual the artery passed dorsal to _M. costi-sternalis anterior_, bifurcating at the normal point. From the ventral trunk of the thoracic artery a variable number of small vessels arises to supply the costosternal articulations. The main ventral trunk bifurcates into two branches, one of which passes onto the inner face of the sternum, and one of which supplies the posterior two intercostal spaces. The dorsal thoracic trunk supplies _M. costi-sternalis_, several dorsal intercostal areas, and the costopulmonary muscles. Minor variations in all of the smaller branches of the thoracic artery were common. MYOLOGY AND ANGIOLOGY: COLUMBIDAE