20 THE GUSTATORY ORGANS, BY TH. W. ENGELMANN. 



(fig. 12, I, i, c) and Key (figs. 7, b, 11, a, d, e). My description is chiefly 

 taken from specimens that were teazed out with extremely fine glass 

 needles, and were either quite fresh, and moistened only with iodine- 

 serum, or which had been exposed for some time to a mixture of equal 

 parts of strong glycerine and 0'4 per cent, solution of bichromate of 

 potash. It was not uncommon for some of the processes to be 

 broken off by this mechanical mode of isolating the cells. The tran- 

 sition of the centric processes of the fork cells into the nerve fibres 



Fig. 279. 



Fig. 279. Surface view of a portion of a gustatory disk from the 

 Frog, after immersion for five minutes in a solution of iodine-serum. 

 Several five or six-angled goblet-cells are seen from above, with the 

 ends of a few columnar cells between them, and a great number of 

 fork-cells in .transverse section. Magnified 600 diameters. 



which emerge from, the nerve cushion, has not as yet been satisfactorily 

 observed. This is chiefly owing to the circumstance that the methods 

 which bring the nerves into view are not adapted for the demon- 

 stration and isolation of the fork- cells, and the two structures are 

 therefore scarcely ever seen equally distinctly in the same preparation. 

 We may sometimes see very beautifully, as is shown in fig. 279, 

 in fresh specimens, optical transverse sections of the prongs of the 

 4 fork-cells in superficial views of the gustatory disks. They then 

 appear as extremely small and bright circles, situated between the 

 five and six-angled broad goblet-cells. We also see the apices of the 

 cylinder-cells as somewhat larger dull circles, distributed amongst 

 the goblet-cells. 



c. GUSTATORY ORGANS OF THE FISH.. 



The gustatory apparatus of the Fish agree in all essential 

 points with that of Mammals and of the Frog. Since the 

 time of Ley dig they have been known under the name of the 



