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The World's Commercial Products 



FRUITFUL VINES 



phylloxera, which has caused, at one time or another, enormous losses in the vineyards 

 of most of the wine-growing countries of the world. Phylloxera vastatrix is an insect belonging 

 to the plant lice family or Aphidae, a group well known for their destructive habits. It is 

 a native of North America, and in Europe first made its appearance in France, appearing 

 later in Italy, Spain, Austria, Germany, and finally in Hungary. Subsequently it caused enor- 

 mous damage in the vineyards of the East, and when the pest again reached the Mediterranean 

 many of the plantations of Algeria were utterly ruined. The Cape of Good Hope was next 

 attacked, and, after nearly ruining the wine industry of the colony, outbreaks occurred in both 

 North and South America. The disease has also appeared in Australia, and practically the 

 only vine-growing country which has hitherto escaped the scourge is Tunis, where stringent 

 measures have systematically been taken to prevent the introduction of the insect. Vines 

 attacked by the phylloxera present a very typical appearance. The plants develop com- 

 paratively few leaves, which are small and quickly lose their colour, becoming yellow or 

 yellowish-brown ; another striking feature is that the edges of the leaves become rolled back. 

 At a later stage the effects of. the disease are noticeable in the grapes themselves, which become 

 arrested in their growth and much wrinkled. 



If the roots of such a plant are exposed and carefully examined with a lens, the cause 

 of the disease becomes evident. The rootlets are seen to bear numerous firm, yellowish. 



