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Page:Popular Science Monthly Volume 72.djvu/370

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366
POPULAR SCIENCE MONTHLY

Icerya purchasi having been at the Cape already for some years a great subject of alarm, the Secretary of Agriculture, at Capetown, made an effort to secure Novius cardinalis from Australia and from New Zealand, but the correspondents to whom he wrote had not been able to collect a sufficient number to make a sending, and a demand was made upon the Department of Agriculture of the United States. Following the year 1891 an ample provision of larvæ and pupæ was sent from California to the Cape. But on account of the length of the voyage, no living specimens arrived. At the end of the same year, Mr. Thomas Low, member of the Legislative Assembly of the Cape of Good Hope, went to the United States, charged by his government with a mission connected with different agricultural questions, and notably to secure the sending of Novius cardinalis. He procured three boxes full of this insect, and left New York the twenty-third of December, 1891. One of these boxes was placed in the ice-box of the steamer. He kept the two others in his cabin, feeding the Novius regularly during the journey with Icerya. The three lots, including those preserved in the ice-box, arrived in perfect condition, and on the twenty-ninth of January were placed in the hands of the Secretary of Agriculture of the Cape.

The insects were then utilized in the following way: a small number were placed in the open air upon an infested tree in the botanical garden at Capetown; but the majority were used for rearings in captivity. Some were placed upon an infested orange tree which was surrounded by a great wire-gauze cage, while others taken to a different locality were placed in a sort of glass house constructed around the orange tree, and similar to those used in California for the same purpose.

The efforts destined to naturalize Novius cardinalis in South Africa were reinforced about the end of 1892 by a new sending coming from Australia, and sent by Koebele, who was then on a mission to that country.

To-day the Novius is perfectly naturalized at the Cape. In some spots which are particularly exposed to cold and where the winter is very vigorous, they succumb to the low temperature, and the Entomological Service is obliged to frequently renew the colonies. This, however, is exceptional, and almost everywhere the Novius, perfectly acclimatized, holds the Icerya in check so efficaciously that since several years they have not worried about it.

Icerya ægyptiaca and Novius cardinalis, in Egypt.—About the same period several attempts were made to introduce Novius cardinalis from California into Egypt, not to fight Icerya purchasi, but an allied species, Icerya ægyptiaca, which is of unknown origin and for several years had been found in the gardens of Alexandria, where it did great damage to the oranges, lemons and figs. The first attempts failed on account of the length of the voyage, but a new attempt made about the