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Show 612 MR. E. B. POULTON ON THE [Dec. 18, xvi. (Plate LIV.) respectively. Glands are very numerous (as they seem to be in connection with the circumvallate papilla? of ah Marsupials), as many as seven ducts being seen in one vertical section (of an anterior papilla); they open at all levels into the involution (see figs. xvi. and xx. Plate LIV.). Peripherally the serous glands are replaced by mucous glands, although the latter are very abundant and sometimes even enter the papillary body. The mucous glands open upon the surface of the organ. In the larger posterior papilla the central nervous mass is ganglion-like (as in Perameles, though not to an equal extent), and nerve-cells occur high up in the papilla, and in still greater abundance in an axial downward extension of the central nervous tissues (see fig. xx. Plate LIV.). This condition was not equally well marked (although present) in the incomplete tongue; and nerve-cells were not detected in any of the anterior papilla?, although they occur in nerves at the base and the downward extensions are present. In all the papilla? of both tongues the dense mucosa beneath the epithelium of the involution is reflected upwards into the papilla, and there forms a protective layer encircling the axial nervous mass (see fig. xx. Plate LIV.). In fact this arrangement is exactly as in Halmaturus, with the same subepithelial layer &c. (compare fig. xxi. Plate LV.). Striated muscles terminate in the dense mucosa at the point at which it curves round to enter the papilla (fig. xx. Plate LIV.). The various possibilities as to the action of these muscles have been discussed (Halmaturus). Here also it is possible that smooth muscle-fibres exist. The arguments apply with greater force to the anterior papilla?, for their shape at once suggests that the mouth of the involution can be closed. There appear to be 1100-1200 bulbs to the square millimetre on these papilla? and the grooves of the lateral organ. The space between the papilla and its involution and the gland-ducts were often filled with a deeply-staining coagulum in the incomplete tongue ; it was probably a constituent of the secretion of the serous glands acted upon by the hardening reagents. There had also been a distinct discharge of a fluid substance from the gustatory pores into this coagulum, in the form of small globules often still connected with the pore by a narrow neck ; the globules were distinct from the coagulum, as they remained unstained. The inferior convexities of the taste-bulbs are prominent and distinct, without any of the filling-in between the bulbs that occurs in higher animals. The bulbs still resemble interpapillary processes. The pores are very short. B. The Lateral Gustatory Organ.-Vertical sections show that the downward direction of the furrows is as irregular as their surface view (see fig. X X X I I . Plate LV.). The serous glands are very abundant, opening at the bottom of the trenches. In one vertical section three ducts were seen. At the sides the serous glands are replaced by mucous glands which open freely on the surface, but never, as far as I observed, into the furrows. Nerves are abundant, and commonly contain nerve-cells collected in small ganglia; they |