Ill 



XVIII. — An explanation of the cause of the Rapid Decay of many 

 Fruits, more especially of those of the Apple and Peach Tribes. 

 By Arthur Hill Hassall, Esq. 



Read October 19, 1842. 



I know not whether the cause of the rapid decay of fruits, more 

 especially of those of the apple tribe, which I am about to relate, has 

 been ere this promulgated or not, but the discovery is, I fear, of too 

 interesting a nature, and one moreover so easily made, that I cannot 

 be the only fortunate observer of it. As it may, nevertheless, be other- 

 wise, I shall proceed to detail the particulars, trusting that I may 

 succeed in imparting to my hearers some portion of the pleasure and 

 interest which I myself experienced on making the observations. 



Before submitting any portion of decayed fruit to the microscope, 

 by means of which many achievments in natural science have already 

 been effected, and to the number of the triumphs of which the present 

 discovery must be added, I observed that the soundest and finest fruit 

 was affected almost as frequently as that of an opposite description ; 

 and that the process of decay did not commence in any one parti- 

 cular situation, beginning as often near the base as the apex of the 

 affected fruit; but that its direction was determined by some bruise or 

 injury which it had received. From these general remarks I was led 

 to conclude that the cause of the decay, whatever it might be, was not 

 of a constitutional but of a local character. With a view therefore of 

 ascertaining the nature of the cause, I placed a portion of decayed 

 apple upon the field of the microscope, and was much surprized to 

 observe vast numbers of ramified filaments, passing between and 

 around the cells of the parenchyma in all directions. Here, then, I 

 at once perceived that a satisfactory explanation was afforded of the 

 phenomenon of the decay of fruits ; that is, supposing the presence of 

 the filaments to be constant. The ramified filaments were to be re- 

 garded as those of a minute Fungus or Fungi, which, by insinuating 

 themselves between the cells of the pulp of the fruit, detached them 

 from their connexion with each other, thus producing a chain of ef- 

 fects, as follow. 



The relation of the cells being disturbed, the process of endosmosis 

 can no longer be carried on, and the circulation through the fruit 

 becomes, as a consequence, either enfeebled or destroyed. The cells 



