^{page 500 note *} The additional sketches, figs. 3 and 4, represent peculiarities in two adult hearts, aud fig. 5, in a fœtal heart, dissected in Dr Handyside's rooms. In fig. 3 a valve (¼ inch broad by ¼ inch deep), formed of endocardium with an intervening lamina of striped muscle, lay within and parallel to the posterior segment of the rim of the superior cava. In fig. 4 is an unusually large persistent Eustachian valve, continuous at its left insertion with a still more remarkable Thebesian valve. The former, which is very large, has an insulated fibrous offset from its left extremity, which runs' half-way across the sinus venosus towards the tubercle of Lower, and then dichotomously divides and subdivides thrice before it is implanted into the arched lino between the right cornu of the Eustachian valve and the right segment of the rim of the superior cava. Fig. 5 represents, in a male fœtus of 6½ months, presented to Dr Handyside's museum during last summer, the occurrence of a complete semilunar valve situated at the termination of the upper vena cava, its convex border being attached to the anterior and right wall of the vein, its concave free border projecting into the auricle.' The right crus of this valve is inserted into the auricular wall on a plane ¼ of an inch behind, and decussating, the right ascending cornu of the prolonged Eustachian valve.