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faction and decay ; to the last of these he applies the term cremacau- 

 sis : and he accounts for its extension from one portion of a body- 

 to another part of the same, or to a neighbouring body, by reference 

 to a remarkable principle, the exact method of the operation of which 

 is however by no means clear, that substances, while undergoing de- 

 composition, cause other bodies with which they are in contact like- 

 wise to become decomposed ; and this, not by virtue of any chemical 

 action which the decomposing body exerts on that, the decomposition 

 of which it effects, but by a kind of induction. As, however, the pro- 

 cesses here mentioned affect only dead organic matter, the principle 

 therefore, so elaborately illustrated by Liebig, does not appear to me 

 to be in any way concerned in occasioning the extension of that pe- 

 culiar form of decay, the subject of the present paper, and which I 

 have stated to involve sound and living portions of fruit. Were how- 

 ever any one of the processes above referred to applicable to it, still, 

 the influence exerted by the Fungi in effecting the decomposition and 

 destruction of fruit, would be in no way lessened or disproved. 



The rapidity of the extension of vegetable mortification depends 

 upon three causes, which I have denominated predisposing ; viz., an 

 over-ripe condition of the fruit ; extremes of temperature combined 

 with moisture, (the effect of which may be seen in apples that have 

 been allowed to remain for a few days upon a lawn in autumn) ; and 

 lastly, a loose aggregation of the cells of the parenchyma : fruit so 

 predisposed passing to decay much more rapidly than such as is of 

 an opposite nature. Thus the firm hard apple, in which the cells are 

 closely compressed, opposes much more resistance to its progress, 

 nor is it so readily subject to its influence. 



Let us now examine the Fungus, or rather, I should say, Fungi, 

 for several species concur frequently in producing the same phenome- 

 non. Two of these I have succeeded in tracing through several stages 

 of their development. In the earliest state in which I have noticed 

 them they consist of innumerable ramified filaments, of extreme mi- 

 nuteness {thallUtS), which, when closely examined, appear to be annu- 

 lated within the outer sheath, so as to convey the impression that they 

 are in reality Conferva and not Fungi, a view which I should unhesi- 

 tatingly have adopted, had I not succeeded in tracing the development 

 of these annulated filaments further. In the second stage of their 

 growth, the filaments are seen to have undergone a considerable in- 

 crease in size, and the annuli are no longer visible. In the next 

 epoch of their development, the ramified filaments {thallus) may be 

 observed to take their origin from the lower portion of a filament 



