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Show 136 ME. F. E. BEDDAED ON DENDEOLAGUS BENNETTI. [Feb. 5, The azygos vein shows considerable differences in different Marsupials ; and I may take this opportunity of putting together the results of some recent dissections. In Dendrolagus there is nothing remarkable, the azygos is on the right side; but in Halmaturus bennetti there are two posterior cardinal veins nearly equally well developed, but longest on left side. In two specimens of this species dissected by m e there were differences; in one the left azygos was much longer than in the other. Petrogale penicillata agreed with Dendrolagus ; so too Macropus rufus. In Phalan-gista vulpina the difference was that the azygos vein was developed on the left side. In one specimen of the last-mentioned Marsupial the azygos opened directly into the vena cava posterior opposite to the entrance of the left kidney vein. The vena cava moreover was very largely absent. This state of affairs did not exist in the other individual. In Didelphys cancrivora and Dasyurus maugcei the left azygos vein was also developed and not the right. In Didelphys azarce the same was the case, only the vein opened posteriorly into the vena cava opposite to renal vein; but the vena cava was not absent in front of this point. § The Brain. I have compared the brain of Dendrolagus with those of Petrogale penicillata and Hedmaturus bennetti. It is about as large as that of the latter and bigger than the brain of Petrogale. The furrows are, however, less marked than in either of the types Fig. 5. Fig. 6. Dorsal aspect. Lateral view. Brain of Dendrolagus. Sy., Sylvian fissure; b anterior, a posterior fissure. |