32 INSECTS AFFECTING THE ORANGE. 



the egg, and probably about twenty days after impregnation of the 

 female. 



"The insects of this brood continued to oviposit until July 1. 



"Number of generations per year. This insect, living on orange trees in 

 a room on the north side of a building in Washington, passed through 

 five generations in less than one year ; the average time occupied by a 

 single generation was a little less than seventy days. It is probable 

 that in the open air in Orange County, Florida, there are at least six 

 generations each year. 



"Habitat. Although I have carefully explored many orange groves in 

 Florida and California, and have had an extensive correspondence with 

 orange-growers, I have been unable to find this species in the last- 

 named State, and have found it only in a single grove in Florida. This 

 is the grove of Messrs. Holmes and Eobinson, near Orlando, in Orange 

 County. The insects were first observed here in the spring of 1879 on a 

 sour-orange tree which was brought from Havana, Cuba, in 1874. On 

 learning these facts I sent specimens to a friend at Havana in order to 

 ascertain if the species occurred there. He at once returned me other 

 specimens with the information that it is a very common pest in public 

 gardens of that city. 



" This species infests the limbs, leaves, and fruit indiscriminately. In 

 the grove of Messrs. Holmes arid Eobiuson it has spread slowly. The 

 large trees which are infested do not seem to suffer much from it, but the 

 young trees are greatly injured by it. Mr. Holmes considers the dis- 

 figuring of the fruit as the worst feature of the pest. The insect has 

 multiplied to such an extent upon the trees upon which I colonized it in 

 my breeding-room, that nearly all of them have been destroyed. The 

 species is certainly one that is greatly to be feared, and there is no 

 doubt that it would be a good investment for the orange-growers of 

 Florida to eradicate the pest, even if in doing so it is found necessary 

 to purchase and destroy all infested trees. This could be done now 

 easily, but if delayed a few years the species will doubtless become per- 

 manently established." 



Since the publication of the above by Professor Corastock, the Ked 

 Scale of Florida has made its appearance at San Mateo upon the St. 

 Johns Elver. Its transportation was accomplished in 1881 or 1882 by 

 means of infested fruit (Lemons), sent from Orlando, and packed for 

 shipment at San Mateo. From the packing-house the pest escaped to 

 orange trees in the vicinity, and soon obtained a foothold in the sur- 

 rounding groves. 



RED SCALE OF CALIFORNIA. 



(Aspidiotus aurantiw Maskell.) 



[Fig. 6.] 



This very destructive pest of the 'Jrauge is known as yet only from 

 California j its introduction into Florida upon imported plants is how- 



