INSECTS INJURIOUS TO AGRICULTURE 367 



beginning of the year 1892 was crowned with success. Six adult insects 

 and several of the larvae arrived in living condition at Alexandria. 

 They were set at liberty upon an orange tree infested with Icerya 

 cpgyptiaca, and accommodated themselves so well to this new food that 

 in a short time they had become so numerous as to cause an almost 

 complete disappearance of the Icerya, But later the Icerya again began 

 to increase. Happily, however, the Novius had not entirely died out 

 and it also recommenced to multiply, and, thanks to the successive see- 

 saw movements between the two species, the Icerya is held in check in a 

 definite way. 



Icerya purchasi and Novius cardinalis in the Hawaiian Islands. — In 

 the Hawaiian Islands, the alarm provoked by the invasion of Icerya 

 purchasi was of short duration. The injurious insect was discovered 

 in 1889 in the suburbs of Honolulu, and multiplied there with rapidity. 

 In 1890, Novius cardinalis was in its turn introduced from California, 

 and a year afterwards the trouble was entirely stopped. 



Icerya purchasi and Novius cardinalis in Portugal. — In 1897, the 

 presence of Icerya purchasi was discovered in the orange groves around 

 Lisbon, and the agricultural population began to be alarmed. This 

 insect had multiplied already for several years along the banks of the 

 Tagus Eiver, and it seemed that the first infested plants had been 

 brought from the Azores, where for a long time the Australian scale 

 insect had existed. 



In 1897, almost all the gardens of Lisbon and its suburbs were 

 infested with Icerya, and the insect was known to occur in 32 locali- 

 ties. Before attempting the introduction of the natural enemies of 

 the Australian insect, they tried insecticides which were found insuf- 

 ficient to stop the scourge, but which, nevertheless, were of much 

 service from time to time, when it was deemed desirable to introduce 

 Novius cardinalis. Messrs. de Silva and Le Cocq were particularly 

 interested in this latter matter. In spite of a hostile press and the 

 opposition of the greater part of the administrative authorities, they 

 placed themselves in relations with Mr. Howard, the learned director 

 of the Bureau of Entomology, of the Department of Agriculture of 

 the United States, and he wrote to San Francisco, to the State Board 

 of Horticulture of California, and procured from Mr. Alex. Craw sixty 

 Novius cardinalis in the adult condition, as well as a certain number 

 of larvae in different stages of development. 



As soon as they arrived in "Washington, in October, these insects 

 were placed in boxes with moss with an ample supply of Iceryas for 

 food, and were then sent on to Lisbon. The greater part of the Novius 

 perished on the voyage. Five only, coming from larvae which trans- 

 formed on the journey, arrived alive at their destination. On their 

 arrival they were placed in breeding cages at the Experimental Agri- 

 cultural Station of Lisbon, and were cared for in such a fortunate way 



