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wafted by the wind, or carried by hands, clothing, insects, animals 

 or empty cases. Thus is the disease rapidly and widely spread. 



It bears some resemblance to another black disease of citrus 

 fruit called " Melanose," and also to a disease known in Italy as 

 " La Nebbia," which is, however, caused by a different fungus. 



The effects of the disease 011 the fruit is that, besides being 

 unsightly and rendered almost unsaleable, they soon become rotten 

 and fall a ready prey to " Blue Mould," etc., so that all such should 

 be rigidly excluded from shipments to distant markets. 



The fungus is found on still green fruit, and spreads most 

 rapidly when the fruit ripens. 



TREATMENT. The skins of diseased fruits should be burnt, in 

 order to prevent the spores reaching fresh-growing fruits. The 

 cases containing diseased fruit should be disinfected by steaming 

 or by dipping in boiling water for a few minutes. Spray the trees 

 with Bordeaux Mixture as soon as the fruit sets, and again every 

 few weeks up to within a month of the time of picking the fruit. 



SOOTY MOULD OR BLACK SMUT. Fumagine follows the attacks 

 of aphides and of scale insects, forming a sooty black membrane, 

 which feeds on the sweet fluids (honeydew) secreted by these 

 insects, and which falls on the leaves, branches, and fruits of the 

 last plant they live upon. 



The growth of the trees affected is retarded in consequence of 

 light and the respiration of the plant being interfered with. The 

 insects further injure the plant by sucking the nutritious juices 

 from the cells, and blooming and fruiting are, in consequence, 

 checked or suppressed, and the market value of the fruit lowered. 



Remedies. Spray two or three times at intervals of one or two 

 weeks in the winter, and after the fruit crop has been picked, with 

 kerosene emulsion or resin and soda ; wash or fumigate with hydro- 

 cyanic acid gas. 



Better still, collect and procure parasites and predaceous insects 

 on the aphis and the scales, which are the primary cause of the 

 sooty mould . When parasites are present, spraying or fumigation will 

 do more harm than good, and will tend, by destroying the beneficial 

 insects, to intensify the trouble. 



ROTTING OF CITRUS FRUIT. Considerable loss is at times ex- 

 perienced during transportation or storage of citrus fruit. The 

 cause is due to one of the blue moulds Penicillium digitatum. 

 This fungus grows on the fruit from a spore, which germinates 

 and penetrates the tissues in the form of white threads, and 

 feeds on the juices ; after a time they show outward as a white 



