ORANGES AND LEMONS IN THE RIVIERA. 481 



The plants are propagated by seed, grafting, cuttings, and layering, 

 principally by the two first methods. When planted in the orchard the 

 distance apart is modified, first, by the kind of culture whether in large 

 orchards, when other plants are to be cultivated between the rows and 

 nature allowed to take its course, or in small gardens, where a system 

 of forcing is used ; second, the quality of the soil, and, finally, the form 

 m which they are to be set out, whether in one row, in squares, etc. 

 In a general way from 15 to 24 feet is near enough for trees of standard 

 size. 



The trees begin to bear flowers and fruit at five years, give a reason- 

 able crop at fifteen, but increase in productiveness up to forty years. 



INSECT PESTS. 



The following insects are hurtful to both orange and lemon trees, but 

 as the lemon tree is always in flower and is more frequently watered, 

 the Lepidoptera in the larva state is more injurious to it than to the 

 orange : 



Coccides. Dactylopius citri (BoisDuval). This insect with soft tegu- 

 ment is very common on both orange and lemon trees of the Riviera. 

 Its body is a red brown; about it are numerous cottony appendices, 

 17 on each side; at the end of the abdomen are two much longer than 

 the others. The insect is entirely covered with white dust. Its length 

 is 0.^03 to O. m 004, breadth O. m 002. The antenna of the female are 8- 

 jointed. The tarsis is half the length of the tibia ; the thread-like feet 

 are very long. Web pores are plenty ; the genito-anal ring large, with 

 6 bristles ; the larva has antenna} 6-jointed ; the abdominal web pores 

 are less numerous than in the perfect insect. The male is long, brown 

 on head and thorax, abdomen yellowish ; the feet and antennae darker 

 in color ; these latter have 10 articulations. Thorax narrow ; elytron 

 very long, grayish white ; abdomen very long, with web pores on the 

 edges ; sexual organs tuberculous in form, quite large, terminated in a 

 rounded point ; feet long ; tarsis longer than the thighs. 



This insect, a veritable scourge, forms upon the young fruit and leaves 

 cottony and sticky heaps, contrasting strongly by its whiteness with 

 the color of the fruit and the black layer of the " Morphe'e," which al- 

 ways surrounds them. Breaking off these living heaps, some of the 

 insects will be crushed, yielding a reddish liquid; in them will be found 

 insects in different stages of development, and besides this the larv 

 of the coccinella and the caterpillar of a little Lepidoptera, the EpUestia 

 gnidiella. 



The Dactylopius citri seeks sheltered spots where the trees, too closely 

 planted, lack air and light. It hurts the growth of the trees by stop- 

 ping the leaf pores. It unites with the Lecanides and the Aphides to 

 propagate " Miellat" and "Morphe"e." 



Aspidiotus limonii (Signoret). This Coccus with hard tegument, 



