AND CONTEXTS OF THE MOUTH. 185 



longest were one-sixth of a millemetre high, equivalent to the 

 thickness of a thin cover-glass, as in the Figs./, g of the figure. 



The colouration of the ears in question with carmine, pro- 

 tracted even for weeks in a watch-glass, gave no satisfactory results. 

 With methyl violet the specimens appear less transparent ; in other 

 respects, they are like those treated with gentian violet. In Fig. 

 1 1 one may be observed, in which the ears are in the direction of 

 the visual axis. With fuchsine the most fine and brilliant coloura- 

 tions are obtained, as shown in the specimen caught in profile, 

 represented in Fig. 1 2, after being immersed for a few minutes. 



In the uncoloured preparations, the ears are hardly or not at 

 all discernible, so that they could not be detected by him who 

 should ignore their existence ; the sporules being, in their natural 

 state, transparent and nearly invisible ; but these preparations are 

 helpful to him who knows them, in so far as they aid to detect, 

 on the outline of the mass, a larger number of ears which have 

 not been spoiled or carried away by the manipulations, or hardened 

 and consequently become brittle. 



Anyhow, the flexibility of the ears is preserved even in the 

 colourings with the solution of iodine, not acidulated, or with 

 picric acid. The sporules appear distinctly with the solution of 

 iodine (Fig. 13); but with picric acid the colouring is diffused and 

 pale, although the pale tint is useful in its turn in disclosing at 

 one time a larger number of fructifications, without rendering any 

 of them opaque. 



Here we shall stop awhile to consider the great affinity of those 

 sporules through the aniline colours ; which affinity brings them so 

 closely to the tubercular bacilli as to make us suspect that the 

 single articulations of such bacilli proceed from the sporules, 

 which, having dropped, transplant themselves into the buccal epi- 

 thelia and the air-passages, and grow like beaded forms. We were 

 led to that supposition from the following fact : — In the colourings 

 with fuchsine of the patina dentaria, which last a very short time, 

 the central portion of many masses remains uncoloured. How 

 great was our surprise in seeing, some time afterwards, in those 

 uncoloured areas, minute red lines, perfectly similar to the tuber- 

 cular bacilli ! Then those coloured lines gradually increased, and 

 we saw the summits of ears developing, as mounds, brilliantly 



International Journal of Microscopy and Natural Science. 



Third Series. Vol. V. o 



