360 The Fungus Disease of India. [part ii. 



we have no hesitation in affirming them to be mere concretions, containing varying 

 proportions of mineral matter in the form of phosphates and carbonates, and, in many 

 cases, combined with a considerable quantity of iron. The presence of carbonates, 

 phosphates, and of iron was clearly demonstrated by the action of re-agents. 



To what their brilliant rosy coloration is due, we are unable satisfactorily to 

 determine ; but, as we shall hereafter see, the fatty matter of the degenerate tissues 

 in the pale variety of the Madura disease has, under certain circumstances, a tendency 

 to give rise to the development of such colouring. The red colouring is, moreover, 

 not an essential character in the concretions, for, as previously mentioned, numerous 

 specimens occurred of precisely similar nature to the most highly coloured ones, 

 save in being of a buif or yellowish hue in place of bright carmine, whilst many 

 other intermediate forms were present showing various degrees of staining. The 

 specimen in which they occurred was preserved in strong glycerine, and there 

 appeared to be a gradual but considerable increase in their numbers whilst it was 

 kept under observation. In studying the conditions under which a development of 

 red colouring matter occurs in connection with the fatty products of the ochroid 

 variety of the Madura disease, we have observed that one of them appears to be 

 the existence of more or less decided acidity, and it is noteworthy that in the present 

 instance the glycerine was distinctly acid in reaction. The results of attempts at 

 cultivation of the red particles will be given subsequently, but in the meantime we 

 would repeat that they appear to us to be mere concretions, probably formed from 

 the degenerated tissues — the proportion of constituents furnished by the latter varying 

 in different instances. Possibly they owe their red hue to a substance analogous to 

 the colouring matter of the blood — just as other pigmentary substances are believed 

 to do. 



CHAPTER VI. 



A DESCRIPTION OF SPECIMENS ILLUSTRATIVE OF THE DARK VARIETY OF THE 

 FUNGUS-DISEASE OF INDIA. 



Having given a minute description of several examples of the pale variety of the 

 fungus-disease, we now proceed to give a similar description of a few typical specimens 

 of the dark variety. Instead, however, of giving a full account of the peculiar 

 substance which is characteristic of all of them, we shall defer the details of the 

 more minute investigations of it until the general appearance of the specimens has 

 been described. This will economise space without sacrificing exactness, for this 

 dark substance does not materially vary in the different specimens. 



Specimen I. — A glance at the accompanying sketch of a longitudinal section of 

 the left foot of a native will convey a more accurate conception of the state of the 

 tissues in this disease than any verbal description. An ordinary scalpel was made 



