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Show 618 MR. E. B. POULTON ON THE [D some little distance behind the tip, are very strongly developed and of a remarkable structure. The powerful horny hooks characteristic of this region are distinct to the naked eye. The free part of the tongue is 19 m m . long (nearly half the total length), and the median ridge below is sharp and the grooves deep. Minute Structure.-I. Gustatory Structures. A. The Circumvallate Papilla.-The transverse sections show that the circumvallate papilla? resemble those of Perameles (see fig. XVIII. Plate LIV.) in their constricted bases. Nerve-cells are abundant in the nerves at the base and probably within the papilla also. The minute structure could not be made out, but I saw some indications of peculiarity in the bulbs and their arrangement. There was an appearance of terminal organs in the papillary processes above the usual limits of the bulbs. The bulbs also seemed to be papillary in position, and were very unusual in appearance. I did not see gustatory pores, but it is most likely that they are present. The above suggestions of peculiarity may be entirely dissipated by the examination of a specimen prepared for histological work. Comparison with the state of the bulbs in Belideus leads me to believe that the peculiarities are not genuine structures, except perhaps the terminal organs outside the region of bulbs. I give no figure because the papilla? were much shrunk. Provisionally these papilla? may be regarded as close to those of Perameles, from their general shape. B. The Fungiform Papilla.-Nothing could be made of the minute structure. The shape, size, and position being normal, it is likely that the structure is also normal. II. Mechanical and Tactile Structures. A. The Coronate Papilla.-The strongly developed papilla? (fig. xi. s.c.p., Plate LIV.) of the patch behind the tip were shown by horizontal sections to be remarkably modified forms of the normal coronate papilla (see fig. x x m . Plate LV.). The posterior secondary papilla? seem to be fused into a single strong recurved horny hook. In other parts of the circle, the secondary papilla? are normal and generally regularly arranged, except for an occasional one or two within the circle. These secondary papilla? are numerous (12-19). Isolated hair-like papilla? also occur abundantly in this region. These modified coronate papillae are large and not very closely placed, so that there are only about 5*5 to the square millimetre. The shape of the posterior hooks, as shown in horizontal sections, is very remarkable. The thick corneous layer is only developed (except where the hook rises above the main papilla) posteriorly to the crescentic papillary upgrowth for the hook (with its concavity directed posteriorly). Posteriorly to the (in section) crescentic upgrowth the epithelial cells become cornified in a thick mass, which anteriorly presents a convexity approximately parallel with the concavity of the crescent. Laterally the thickened corneous mass is |