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no account should tlie ditcli be opened before the lapse of six months, 

 when the insects and cocoons will be dead, and the rotten fruit will be 

 found to afford a good compost for the orange groves. 



The Toxoptera AuraDtii or Aphis Aurantii is particularly harrassing 

 to the new shoots of young orange trees, although it is common to see it 

 on large fruit bearing trees. The young leaves infected with this insect 

 develop themselves irregularly, become wrinkled and curled. The flowers 

 drop without blooming or soon after blooming and the tree is greatly ex- 

 hausted. This Aphis has many enemies among which are the lady* 

 birds and the laceflies already noted, — and were it not for this, its 

 prodigious power of increase would soon make orange culture an im- 

 possibility Tobacco decoction, tobacco fumigation, soot, spraying 

 with cupric solution, with petroleum emulsion, &c., are equally efficient 

 methods of getting rid of this insect. 



The Scale insects are the most familiar of all pests of the orange 

 grove. They are generally of a small size, but their vast numbers 

 make them conspicuous even at a distance They increase with such 

 marvellous rapidity, as to cover whole orange groves in a few 

 days ; so that even when the trees appear almost clear of scale insects, 

 with favourable weather a new outbreak of the disease may be ex- 

 pected. 



The White Scale insect Aspidiotus Limoni is rarely seen on the 

 orange tree It is as small as a pin's head; of a flattened conical shape, 

 and perfectly round. The scale itself is transparent, the body of the 

 insect appearing as a yellow dot ifl the middle of the scale. When 

 this insect is very numerous, the scales can be obtainad in large flakes 

 sticking together. Another form of Aspidiotus is the A. Nerii which 

 is found more often on the Oleander. The male insect is smaller than 

 the female, and a portion of its life is passed as a scale insect but 

 having undergone the third month, it issues forth a small gnat-like 

 insect, multitudes of which are constantly hovering in swarms among 

 the orange trees. 



The large black Scale insect, Lecanium Olese is an old foe of our 

 orange groves. For its permanent abode it select the green twigs, and 

 is seen but seldom upon the leaves. It is a black, wrinkled scale of 

 the size of a small pea, nearly hemisphaerical in shape. When young, 

 the almost invisible larva wanders upon the foliage and twigs of the 

 orange tree. After a few hours of this wandering life, it seeks, for 

 itseK a suitable place where it fixes itself, loses its legs, and secretes a 

 flmall waxy scale which covers its whole body, and which increases in 

 size with each moult. 



The Mytilaspis citricola is another scale insect having the form of a 

 grain of sesame or of a comma. It is deep brown ; its variety Mytilas- 

 pis flavescens being light brown. At the pointed extremity of the 

 scale is found the head of the insect, whose mouth consisting of two 

 mandibles and four bristles, is immersed in the substance of the leaf 

 eagerly absorbing the sap. This scale insect is more commonly seen on 

 the green parts of the tree, sheltered from the direct rays of the sun. 



The small black scale insect, known as Parlatoria Lucasi, is a flat, 

 black scale of an elliptical shape, surrounded by a white waxy margin, 

 and having at one extremity, where the head is found, a black dot-like 

 small scale which is the first tunic secreted by the insect, soon after it 



