280 [ DISEASES OF THE APPLE TREK 



or tar. Nessler's tincture often recommended against 

 this parasite, consists of 30 gr. soft soap, 2 gr. sulphide 

 of potash (liver of sulphur) and 32 gr. of fusel oil 

 (amylic alcohol) dissolved in i litre of water. 



Three species of Psylla (plant-fleas) are found on 

 the apple, viz: l^sylla Mali Schmid., P. melanoneura 

 Forst, and P. pirisuga Forst.; of these only the first 

 is occasionally met with in our orchards P. Mali is 

 yellowish green, the female insect having a red thorax 

 with brown lines, the antennae are yellow with a long 

 and pointed frontal process. The wings are almost 

 transparent with yellowish nerves. This insect attacks 

 the young foliage and the growing twigs, but is easily 

 controlled by spraying with a i per cent solution of 

 borax, or by whitewashing with lime in winter. 



Typhlocyba Rosae (L) Germ, is sometimes found 

 on the apple tree sucking the sap of the leaves and 

 of the blossoms. It is 4 m.m. in length, of a pale 

 yellow colour, with transparent elytra, and white wings 

 with a bluish shine. It is never so numerous as to 

 become dangerous. The larva of a small fly, Agromyza 

 minuta Meig. (Diptera), excavate long tunnels close 

 to the extremity of the leaf, but this insect has not 

 been detected so far in local orchards. The fruit- fly 

 (Halterophora or Ceratitis capitata}, very often punctures 

 the fruit of the apple, depositing a small cluster of 

 eggs in each puncture; but these eggs rarely develop, 

 and the puncture as a rule soon heals, leaving a 

 hardened dark spot in the rind and in the flesh of the 

 apple. The fruit as a result of this puncture is dis- 

 figured and its keeping qualities are impaired, but the 

 development of the larva of the fly in the apple has 

 been noted only in rare instances. -.. % 



The Lepidoptera include a host of species which 

 are injurious, and sometimes dangerous, to the apple 

 in continental orchards. Irregular tunnels in the shape 

 of small spots are produced on the upper surface 



