596 [ DISEASES OF THE VINE. 



this pest are certain species of Convolvulus, and it lives 

 chiefly on their underground stems, and roots, whence it 

 passes frequently to the roots of the vine, inducing a 

 state of exhaustion owing to which the plant may 

 succumb. 



The vine-aphis, Aphis Vitis Scop is green and 

 brown, and occasionally attacks the tender foliage late in 

 summer in France and Italy. A. Persicae Fons. is an- 

 other species which attacks the vine in these Islands as 

 well as in Southern Europe. 



The Phylloxera of the vine (Phylloxera vastalrix, 

 Planckon) has acquired an evil name on account of the 

 vast destruction which it has caused in almost all coun- 

 tries where the vine is cultivated, 'ihis insect was first 

 described by Asa Fitch in 1854 under the name of Pem- 

 phigus viti/olii, a name which he applied to the insect 

 in its larval stages within the galls en the foliage of 

 American vines in the neighbourhood of New York, and 

 subsequently received other names, until it was fully re- 

 described by Planckon and placed among Aphids in the 

 genus Phylloxera of Boyer de Fouse. It was first noted 

 in Europe in 1863, when it was described by Westowood 

 from specimens found in the greenhouses at Hammer- 

 smith near London, where it was introduced on the roots 

 of infected vines from Atnerica. Soon afterwards it was 

 observed in France, and in 1865 it was detected in 

 Portugal. In 1879 the Phylloxera was found to exist 

 in Italy, Australia, and in a few years more it had spread 

 to vast regions in France, Italy, Germany, Austria, 

 Hungary, Russia, the Balcans, North Africa, South 

 Africa, etc. In 1880 it had already passed to Sicily, but 

 for a long time the Maltese Islands continued to enjoy 

 perfect immunity . from this disease. Unfortunately in 

 July 1919 it was found that a considerable centre of in- 

 fection existed at Ramla (Gozo) as well as smaller 

 centres here and there in that Island, so that the local 



