148 
DR. A. WALLER ON THE MINUTE STRUCTURE OF THE PAPILLA 
of a granular mass of a convex form, which, when viewed at the edges, appears sur- 
rounded by a fringe of epithelial cells, which is detached after a short maceration. 
The conical papillae rarely exceed the y^^th of an inch in height. Maceration 
causes them to swell considerably, so as to attain more than double their original 
size. The greatest increase is at their summit or free extremity, and the papilla 
then assumes a flask-like form. Some of the epithelial cells likewise attain an ex- 
traordinary increase of size by maceration. 
Description of the Plate. 
PLATE XII. 
A portion of the frog’s tongue removed from the border near one of the tubercles, 
as viewed with a magnifying power of 350 diameters, under a slight compres- 
sion. 
A. Fungiform papilla, projecting along the margin. 
B. B. Conical papillae, projecting along the margin. 
C. Border of the tongue with vibratile cilia, seen in constant movement over 
the fungiform papillae. The depression in the border is the commence- 
ment of a channel formed by the rugae so numerous near the edges. 
D. Small mucous follicle. 
E. Apertures of the conical papillae. 
F. A capillary vessel containing blood-discs and corpuscles, ascending half- 
way up the papilla conica. 
G. External zone of fungiform papilla, formed of epithelian cells which are 
much more indistinct and laminated over the neuro-vascular area. 
H. Neuro-vascular area containing the capillary, the gustatory nerve, and 
striated muscular fibre. 
I. The capillary ascending from the lower surface of the tongue towards 
the fungiform papilla, wherein it forms coils, making its exit in the 
same direction in which it entered. The vessel is represented in a 
state of engorgement, the globules compressed and indistinct. 
J. The gustatory nerve, likewise derived from a branch near the inferior 
surface, entering the papilla between the capillary. Near its entrance 
it makes numerous wavy bends of a spiral form. The tubules become 
more distinct and diffused towards their extremities, where they appear 
to be composed of separate joints from the coagulation of the medulla 
of the tubule. Their extremities in this example appeared all of them 
to be slightly dilated, and with a dark point at their termination, giving 
them the appearance of ending in open mouths. 
K. Striped muscular fibres ascending vertically into the papilla among the 
vessels and nerves, becoming indistinct near the summit. 
