The object of this paper is to state the result of observations on the metamorphosis of the great anterior veins in Man and Mammalia, and on the relations existing between the primitive and final condition of these vessels, in different cases, both in their normal arrangement in animals, and their abnormal condition in the human subject. From an examination of the form and structure of the sinus of the great coronary vein, and of the arrangement of its branches and valves in Man and some of the Mammalia, and from a comparison of those parts with the terminations of the great coronary and other posterior cardiac veins in the other Mammalia, the
coronary sinus
in Man and one set of Mammals, as the Dog, Cat, and Seal, is shown to be
analogous to the lower part of the left vena cava anterior
found in another set, represented by the Elephant, Rabbit and Hedgehog, and to
the lower part of the left vena azygos
, found in a third set, as exemplified in the Sheep, Ox and Pig. The great coronary vein, therefore, is shown always to end in a similar way, viz. in a larger muscular venous channel, which, in all cases, ends in the right auricle of the heart, by a wide orifice situated in an exactly corresponding part of that cavity.