No. 2.] ON THE GUSTATORY ORGANS. l6l 



The MecJiaiiical Papilla:. — These papillae differ to some ex- 

 tent from the compound filiform papillae of the marsupial tongue. 

 The secondary papillx are fewer in number, there being not 

 more than five or six to a papilla as a rule, and resemble some- 

 what the stout, hard spines of the Carnivora. Many of the 

 papillae bear at each lateral border a single recurved spine, the 

 space between being packed with epithelium. When viewed 

 in horizontal section they present a horseshoe-shaped cavity. 

 These papillae may be looked upon as representing an interme- 

 diate type between the "coronate" and "fasciculate" papillae of 

 the Marsupialia and the corresponding papillae of still higher 

 forms. Another and more simple form of papilla occurs on 

 this tongue near the lateral margins. It consists of a single 

 papillary upgrowth of the mucosa, overspreading which is a 

 layer of stratified epithehum. From the bed of epithelium 

 rises a single sharply pointed spine. The spine is cornified at 

 its upper part, and directed inwards and backwards. 



Gustatory Structures. 



The Circwnvallate PapillcE. — The papillae were not devel- 

 oped alike in all the specimens. While some of them resemble 

 the papillae of higher animals, others approach more nearly the 

 marsupial type. The former, or more recent type, are 1.3 mm. 

 in diameter and i.i mm. in height. They are flattened on top, 

 and barely reach the level of the lingual surface. The bulbs are 

 disposed around the lower part of the lateral area in eighteen 

 closely packed tiers. The circumvallate papillae of less recent 

 type are taller than the foregoing, and their sides converge as 

 they approach the opening of the trench. Their lateral area is 

 filled with bulbs to within a short distance of the top, there 

 being often thirty tiers of them. They measure 0.051 mm. in 

 length and 0.030 mm. in breadth. Serous glands are quite 

 abundant, the ducts opening into the trenches at their base and 

 sides. 



The Lateral Gustatory Orga7is. — The lateral gustatory organ 

 of Dasypiis villosus is not unlike that of Procyon lotor (described 

 by the writer in the "Journal of Anatomy," Vol. XXIV., 1890). 

 The superficial examination of this region showed several irreg- 

 ular slit-like openings, but I only succeeded in obtaining sec- 

 tions through one of them. This opening was 0.20 mm. in 



