i9o6.] Preventing the Decay of Ripe Fruit. 563 



No special selection was exercised in procuring the fruit for 

 experiment. The plums, cherries, grapes and pears were pur- 

 chased at a local fruit shop, and the gooseberries and bananas 

 were obtained from a street vendor. In each case a certain 

 portion of the fruit was treated with formalin ; this was placed 

 alongside an untreated portion on a plate of glass ; the two 

 were covered with a bell-jar, and exposed to the ordinary 

 temperature of the laboratory. 



The following table shows the number of days that treated 

 fruit remained perfectly sound and free from mildew, after ^the 

 untreated check fruit had become covered with mould and quite 

 unfit for use : — 



Plums (Damson 9 days. 



10 ,. 



I Victoria 



Bananas 



Black .., 



Currants . ^.^^ 



Cherries 



... 7 days 



Gooseberries ... 



7 M 



Grapes... 



... 4 



Pears 



... 10 



Strawberries ... 



• •• 4 „ 



The following table shows the kinds of fruit used last year 

 for testing the preservative properties of formalin, and indicates 

 the number of days during which treated fruit remained per- 

 fectly sound, after the check or untreated fruit had become un- 

 fit for use. The first column of figures refers to last year's 

 experiments, the second column to this year's corroborative 

 experiments : — . 



... 8 days. 



6 „ 



6 „ 



9 „ 



5 



It is important to remember that all the kinds of fruit experi- 

 mented upon were quite ripe and had been exposed for sale, and 

 were consequently exposed to infection, and that in some in- 

 stances they were more or less bruised. With fruit carefully 

 gathered and treated at once, the duration in a saleable con- 

 dition might be anticipated to extend over a longer period than 

 is indicated by these tables. 



In the case of apples that are just pitted with disease, treat- 

 ment with formalin proves of service. Apple rot, caused by^the 

 fungus called Glceosporiimi fructigenuni^ Berk., is very destruc- 

 tive to ripe fruit, on which it first appears as minute scattered 

 spots on the skin ; these spots rapidly extend and form large, 

 brown sunken patches ; within a very short time this fungus 

 reduces the fruit to a brown, rotten mass. A dozen apples 



