Non: ] GUSTATORY ORGANS OF THE BAT. 5 
far the most interesting specimens (which are shown in Fig. 6) 
were found in a papilla from the posterior region of the tongue. 
In this papilla there are two well-formed bulbs, and placed 
between them is a third, which is either of a low order or unde- 
veloped. The largest bulb of the three measures 0.036 mm. in 
length and 0.016 mm. in breadth, and its apex appears to reach 
the free surface of the epithelium, its base penetrating the 
mucosa. Some of the isolated bulbs met with elsewhere in 
these papillae, particularly those of the anterior dorsal surface, 
are even larger than those shown in Fig. 6. Neither serous nor 
- mucous glands were observed near the fungiform papillz. 
The entire upper surface of the tongue is covered with papillz 
of mechanical and tactile (?) function. They are quite closely 
set, except at the basal region, are largest at the posterior part 
of the dorsum, and gradually decrease in size as they approach 
the anterior extremity. These papilla, when near the tip, en- 
large slightly again. One from the posterior third of the tongue 
measured 0.11 mm. in height and 0.04 mm. in breadth. Behind 
the circumvallate papilla, and also about the tip, are numerous 
rather coarse, retroverted, conical papillae. Each papilla is 
seated upon a single papillary upgrowth of the mucous mem- 
brane, and is invested by epithelium of a uniform thickness. 
The outer layers of epithelium covering the upper surface and 
sides are usually partly, and occasionally wholly, cornified. 
These papillae vary much in shape and general appearance. 
Many of them are cone-shaped, while others resemble, in ex- 
ternal structure, minute fungiform papillae. The upper surface 
is now and then flat or slightly convex, but usually the papilla 
terminates in a retroverted, horny spinule. 
1 Figure 7 represents a vertical section through a fungiform papilla, from the ante- 
rior dorsal surface of the tongue of a pig, containing eight taste-bulbs. 
