618 MR. E. B. POULTON ON THE [DeC. 18, 



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 mm. 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 Papillce. — The transverse sections show that 

 the circumvallate papillae 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. Com- 

 parison 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 be- 

 cause the papillsB were much shrunk. Provisionally these papillae 

 may be regarded as close to those of Perameles, from their general 

 shape. 



B. The Fungiform Papillce. — 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 Pa^nllce. — The strongly developed papillae (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. xxiii. Plate LV.). The posterior secondary 

 papillae seem to be fused into a single strong recurved horny hook. 

 In other parts of the circle, the secondary papillse are normal and 

 generally regularly arranged, except for an occasional one or two 

 within the circle. These secondary papillae are numerous (12-19). 

 Isolated hair-hke papillae also occur abundantly in this region. 

 These modified coronate papillse 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 up- 

 growth the epithelial cells become cornified in a thick mass, which 

 anteriorly presents a convexity approximately parallel with the con- 

 cavity of the crescent. Laterally the thickened corneous mass is 



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