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Show 328 ON THE HEART IN ORNITHORHYNCHUS ETC. [Apr. 21, partly forced its way out of the body of its enemy, making its three inches from the mouth. The Amphisbsenoid was besides interesting for the anomalous scutellation of the upper surface of the head, the sutures between the ocular, supraocular, and one of the temporals on each side, which were normally distinct in L. polystegum, being obliterated, as was shown in the accompanying sketch (p. 327),; the frontal shield was also remarkably small. Mr. Seebohm exhibited specimens of a Cormorant from Japan believed to be Phalacrocorax capillatus (Temm. et Schl.) and to be quite distinct from Ph. carbo. The following papers were read :- 1. On the Structure of the Heart in Ornithorhynchus and Apteryx. By Sir R I C H A R D O W E N , K.C.B., F.R.S., F.Z.S., & c [Eeceived March 11, 1885.] The • Note' communicated by Prof. Ray Lankester to the Scientific Meeting of the Zoological Society, March 3rd, refers to the description and figures of the heart of the Apteryx in the " Anatomy " of that bird recorded in vol. ii. of the ' Transactions' of the Society, 1836, pp. 271, 273; plate vi. figures la, 2, and 3. These were taken in the dissection of the trunk and viscera of a male bird transmitted from New Zealand, in spirit, and well preserved for anatomical investigation (op. cit. p. 258). Figure 1, of pi. vi., shows the pericardium containing the heart, in situ, showing the apex protruding through the diaphragm into the abdomen ; figure 2, ib., shows the outer form and avian symmetrical disposition of the bifurcate ascending aorta; figure 3 shows the internal structure of the right " auricle and ventricle." The principal deviation from the ornithic type of " the heart's structure is presented by the valve at the entry into the right ventricle," whereon I remark:-"We perceive in this mode of connection an approach, in the present wingless bird, to the mammalian type of valve, analogous to that which the Ornithorhynchus offers, iu the structure of the same part, to the class of birds ; for the right auriculo-ventricular valve in the Ornithorhynchus is partly fleshy, partly membranous" (op. cit. p. 273). I heard, with pleasure, the confirmation by Prof. Ray Lankester, in his earlier 'Paper' (P.Z.S. 1882, p. 549), of the discovery recorded by me in Trans. Zool. Soc. vol. ii. p. 273. Before sending the account of it to press, I had the opportunity myself of confirming it, by receiving a third specimen of Apteryx sent to me for dissection. In this well-preserved specimen I found the same approach to the monotrematous type of heart; it yielded confirmation of the previous dissection of the bird, and the additional materials (torn. cit. p. 258), recorded in Trans. Zool. Soc. vol. iii. |