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Show 1883.] TONGUES OF THE MARSUPIALS. 609 The coronate papilla? are generally circular and very large (about five to the square millimetre) ; they are not closely packed as in the region to be next described. The posterior side can be recognized by the same character that it presents in the papilla? of the tip. There are generally 6-8 secondary papilla? in the anterior horseshoe ; the arrangement is occasionally irregular. Between the anterior circumvallate papilla? there are no isolated hair-like papilla?. The coronate papilla? possess very complete rings of secondary papilla? (13-17 are the common numbers, and 17 is not at all uncommon). The rings are very symmetrical, and the posterior side is not much marked, though generally recognizable by the higher level at which the secondary papilla? arise. The coronate papilla? are generally circular and are very closely packed (about seven to the square millimetre). In one section the papilla? were about *375 m m . in diameter, and the spaces between them from *075-*025 in width, and most frequently the latter. Longitudinal vertical sections show that the coronnte papilla? in this region are beautiful and tall, with their hair-like papillae slightly recurved at the tip (see fig. xxvi. X 14*5, Plate LV., which shows one of these papilla? in perspective). They are over 2 m m . in height (from the top of a perfect secondary papilla to the surface of the superficial epithelium of the tongue). The upper cells of the main papilla stain deeply like those of Perameles and many other Marsupials. B. The Filiform Papilla.-Probably normal in structure, but no minute investigation was possible. Thus this tongue decidedly follows the type of Halmaturus, but it shows an advance in all the points which the two have in common. THE TONGUE OF Petrogale xanthopus. I have recently received a fresh specimen of this tongue, so that I am able to add a general description. The whole tongue is strikingly similar to Macropus, and, like it, follows the type of Halmaturus. The circumvallate papilla? are arranged in a similar triangle (the posterior angle being very obtuse), and nothing can be seen from the surface except the orifices of the involutions. The posterior papilla appears to be rather different from the anterior, the entrance being extremely small (probably contracted), and lies in the centre of a raised subcircular area, of which the surface is smooth. The anterior openings are larger (probably less contracted), and the raised area is less distinct. The fungiform papilla? are arranged as in Macropus, along the sides and tip, where some of them are larger ; a few are scattered on the upper surface, and these may also be present in Macropus in the fresh state. The lateral organ is not arranged in the segment of a circle (as in Macropus), but apparently forms an irregular line of openings which are not raised upon elevations. The line is of considerable length, and the depressions are separated by more than the usual interval. The openings were very contracted, and could hardly be made out on the left side. No |