GUSTATORY ORGANS OF MAN AND MAMMALS. 13 



processes of the gustatory cells. Schwalbe sometimes saw very 

 similar fibrils project from the surface of the mucous membrane 

 in specimens prepared in chromic acid from which the epithe- 

 lium had been brushed away. 



The relations of the nerves in the gustatory ridges of the Rabbit and 

 Hare are very similar to those of the papillae circumvallatae. The 

 numerous and moderately thick branches of the glossopharyngeal 

 nerve, which ramify beneath the gustatory lamellas, contain tolerably 

 large, though still only microscopic, clusters of cells. In one of these 

 I counted more than thirty cells. These were quite spherical, with an 

 average diameter of 0'05 of a miUimeter, and appeared to be in 

 connection with a nerve at one pole only. From the larger nerve 

 trunks, very numerous and still moderately thick fasciculi of pale 

 fibres proceed towards the zones of the gustatory bulbs. Wherever 

 these are situated, though not elsewhere, the mucous membrane 

 contains numerous nuclei (fig. 271, where this character is indicated 

 by dotting, and fig. 269). In this nucleated layer extremely 

 numerous, very fine, pale nerve fibrils run, which agree in size, form, 

 refractive power in regard to light, and, as it would appear, also in 

 chemical relations, with the central processes of the gustatory cells. 

 They may not unfrequently be followed to the base of a gustatory 

 bulb, where they are lost. 



As an appendix to the foregoing, we may here consider the descrip- 

 tions given by Szabadfoldy and Letzerich on the mode of termination 

 of the gustatory nerves of Mammals. According to the former 

 observer, they end in pyrifonn corpuscles that are imbedded in the 

 connective tissue of the mucous membrane. But inasmuch as they 

 cannot be in any case immediately touched by the substances passing 

 through the oral cavity, whilst at the same time the gustatory sensa- 

 sions are perceived much earlier than it is possible for any known 

 solution to permeate the thick epithelial layer, it is obvious that 

 the structures described are not gustatory organs at all, as Szabadfoldy 

 maintains. Moreover other observers have not been able to discover 

 them. Nor have the statements of Letzerich, up to the present time, 

 received greater support, according to whom the gustatory nerves in 

 all the papillae of the Cat, Ox, and Weasel terminate in " flat tolerably 

 large vesicles, the walls of which are structureless, and beset with 

 large nuclei. These vesicles lie upon the mucous plexus of the lingual 

 and papillary mucous membrane." They have two kinds of processes, 

 one of which is nipple-shaped, directed towards the connective tissue 



