INSECTS INJURIOUS TO AGRICULTURE 365 



In 1894, at the opposite extremity of the United States, in the 

 State of Florida, a new invasion of Icerya purchasi was produced, and 

 the scale insect was introduced, this time under conditions which show 

 very well the risks attending such attempts to acclimatize useful insects 

 when they are made by incompetent persons. A nurseryman in Hills- 

 boro county, Florida, having heard of the extraordinary services ren- 

 dered by the Australian ladybird, being ignorant of the fact that this 

 insect will not attack other insects than Icerya, sent to California for 

 Novius cardinalis to fight the Aspidiotus, or other scale insects, feeding 

 upon their plants. The Novius was naturally sent with some Iceryas 

 which would serve as food for it on the journey, and they were all 

 placed together by the nurseryman upon the trees which he desired to 

 protect. No one knows what became of the Novius, but the Icerya 

 multiplied and was not slow in covering the trees upon which it had 

 been placed. Eadical measures were almost immediately taken ; all the 

 trees attacked were burned ; and for four years nothing was heard of the 

 insect. It was believed to have been entirely exterminated, but in 189.8 

 the presence of specimens of Icerya was discovered. The formidable 

 scale insect was found at this time at several points near the locality 

 where it had been first imported, and it had invaded one or two orange 

 groves. It was necessary to give up all hope of exterminating the 

 species, and an immediate effort was made to introduce Novius 

 cardinalis. 



Mr. Gossard, state entomologist of Florida, and Mr. Al. Craw, 

 entomologist of the State Board of Horticulture of California, directed 

 the work. The Novius was at first colonized with success in two of the 

 infested orchards, and in 1900 had become sufficiently well established 

 to enable them to distribute it in good number in infested localities. 

 It seems to be certain that Icerya finds in Florida conditions less favor- 

 able to its development than in California. It has been stated that it 

 is attacked there by a fungous disease. In any event it can not be 

 doubted that with the assistance of Novius cardinalis, it will never play 

 in Florida the injurious role which it has played on the Pacific coast. 



America is not the only country which has suffered from the intro- 

 duction of Icerya purchasi. This insect has been imported, or was 

 imported at almost the same time, into South Africa; and more recently 

 it has made its appearance in the Sandwich Islands, in Portugal and 

 in Italy. Novius cardinalis has in these cases been sent for, and the 

 success has been as complete as that obtained in California. 8 The his- 

 tory of these successive invasions and of the efforts which have been 

 made to combat them conveys useful instruction and is worthy of our 

 attention. 



Icerya purchasi and Novius cardinalis at the Cape. — About 1890, 



8 Novius cardinalis has also rendered great service against Icerya in New 

 Zealand. 



