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Show 1895.] LUNGS OP SNAKES, AMPHISB.ENID.E, ETC. 703 sumption in favour of our finding the left lung the larger, I should like to know that the statements to the contrary were based on an inspection of the lungs in situ before considering the point decided *. V. ON THE SMALLER SIZE OF THE LEPT LUNG IN (1) CERTAIN SNAKE-LIKE LIZARDS AND AMPHIBIANS AND (2) CERTAIN MAMMALS. Having noticed that the Amphisbaenidae differed from Snakes having their right lung, and not their left, reduced or absent, I was led to examine various other snake-like Lizards and Amphibians to see whether they in this respect agreed with the Amphisbaenidae or with the Snakes. A reference to the list given (p. 706) shows that I find that in all the lizards examined if one lung is smaller it is the left, and the same is true of the Gymnophiona examined, which is in accord with Wiedersheim's account based on more extensive acquaintance with tbis group. Lastly, in many (according to some authorities in most2) mammals the right lung is larger than the left, sometimes considerably larger 3. With the exception of Snakes, certain snake-like Lizards, Gymnophiona, and some mammals, all vertebrates, I believe, have both lungs well developed and either equal or differing but slightly in size; and the Amphisbaenidae appear to be the only animals in which the right lung is rudimentary. 1 Specimens of Chirotes being scarce, our knowledge of the soft anatomy probably derived chiefly from specimens which have been sacrificed to make skeletons, such organs as the lungs being put up separately in spirit. Of course descriptions based on such preparations would be unreliable as evidence on the point in question. Flourens's figure is ostensibly drawn from such a preparation ; while that Meckel (and apparently Duvernoy also in one instance) has made incorrect statements as to the right und left lungs of other animals I have shown above (p. 694, and note 4 on p. 695). There is, it seems, no dissected specimen of Chirotes in London. I have tried by writing to what seemed a likely quarter to ascertain whether there exists in Paris any preparation showing the visceral anatomy of Chirotes, but so far without success. It is to be hoped that anyone who is able to dissect this rare form will sketch the organs in situ. 2 Thus Gr. L. Duvernoy, ' Lec,ons d'Anatomie comparee de Georges Cuvier,' 2nd ed. torn. vii. pp. 20, 24, 25 (Paris, 1840). H. Milne-Edwards, 'Lec^ns sur la Physiologie et 1'Anatomie comparee de l'Homme et des Animaux,' torn. ii. p. 334 (Paris, 1857). 3 Thus the preparations exhibited at the Royal College of Surgeons show the right lung markedly the larger in Talpa europcea, Mus decumanus, Notoryctes typhlops, Hyrax capensis, Synetheres (Cercolabes) mexicanus, and markedly so in various other mammals. 45* |