TONGUE AND GUSTATORY ORGANS OF MEPHITIS MEPHITIOA. 151 



Jourdan quite recently (18) has pointed out on the gills and 

 in the buccal cavity of the malarmat, cup-shaped bodies com- 

 posed of central and peripheral cells, which, in structure and 

 situation, differ completely from the organs of touch, and 

 which he regards as taste-bulbs. 



In 1858, Billroth (4) described the peculiar epithelium of the 

 taste papillae of the frog, and believed that certain of its cells 

 were continuous with nerve-fibres. The smaller papillae he 

 thought were unprovided with nerves. 



Hover (16) differed from Billroth in supposing that the 

 nerves terminate bluntly beneath the epithelium. 



In 1861, Key (19) described in the frog two kinds of cells 

 at the summit of the fungiform papilla, — epithelial cells and 

 taste-cells. He speaks of the penetration of the axis cylinder 

 alone into the papilla, and its division into fibres which enter 

 the taste-cells at its summit. The "nerve-cushion" of Engel- 

 mann he considered an enormous enlargement of the neuri- 

 lemma and called it the " nerve-shell." 



Hartmann (10) thought that the nerves ended in plexuses 

 beneath the epithelial cells of the fungiform papillae. 



Beale (2), Engelmann (7), and Maddox (29) supported Key, 

 believing in a structural continuity between the cells at the 

 top of the papilla and the nerve-fibres in its axis. The former, 

 however, did not consider the cells to be of epithelial origin. 



In 1868, Engelmann (8) described, in the fungiform papilla 

 of the frog, numerous dichotomous subdivisions of the nerve- 

 fibres, which form a close network and spread out in the lower 

 half of the " nerve-cushion " in nearly a horizontal direction. 

 The upper part of the papilla consists of a solid disc composed 

 of non-nucleated connective tissue, which he calls the " nerve- 

 cushion," and upon which rests the taste disc. The latter is 

 composed of three distinct kinds of cells, viz. cup-shaped, 

 cylinder, and forked. The two former he considered were 

 epithelial cells only. The forked cells he regarded as the end- 

 organs of the gustatory nerve, probably being directly con- 

 tinuous with pale nerve-fibres, which in their chemical reaction 

 they resemble. Engelmann says that the nerve-fibres jus* 



