THE PLUM ] 357 



midrib small pocket-shaped galls are caused by the 

 yellow larvae of Cecidomiya Pruni Kalt. 



The scale insects Mytilaspis pomorum Bche. and 

 Aspidiotus Hederae Vallot. are frequent parasites of the 

 plum, which in continental Europe is also liable to infe- 

 station by Lecanium Persicae Lin. Another species of 

 Lecanimn, probably L. Prunastri Fonsc. is common 

 on plums and apricots in local orchards, and badly 

 infested trees may be submitted to winter treat- 

 ment with sulphur lime wash or simply with ordinary 

 whitewash applied twice with an interval of fifteen days. 



The fruit-fly Ceratitis capitata Wied attacks the fruit 

 of late ripening plums, but except in the case of Tardive 

 Musquee whose peel is very thin, the injury caused to 

 other plums is quite unimportant. 



The moth Diloba caeruleocephala Lin. occasionally 

 attacks the blossoms and foliage of the plum, but as the 

 larva hatches and develops on the almond long before 

 the plum is in leaf, it is probable that its presence on the 

 plum is merely accidental, and due to the close proximity 

 of almond trees from which the larva has migrated in 

 quest of food. 



There are many species of moths and butterflies 

 which attack the foliage of the plum in Italy and other 

 continental countries, and probably there are several 

 species of moths, particularly of the Microlepidoptera 

 which prey upon the plum and the apricot in these 

 Islands, but the injury caused by them is never so im- 

 portant as to become dangerous or even to attract much 

 attention. Zeuzera Aesculi Lin. attacks the stems and 

 branches of the plum in Italy and in Germany, but 

 though frequent in our orchards on the apple, the pear, 

 the pomegrante etc. it is not known to attack the plum. 



Bostrychus dispar Fb. is a small beetle known to be 

 injurious to our plum trees in a weakly condition, 

 but in continental Europe the following species of 



