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368
POPULAR SCIENCE MONTHLY

that in the month of December they had already a numerous progeny.

On the twenty-second of November a second colony of Novius was sent to Lisbon. The journey this time, on account of accidental delays, was particularly long, and from San Francisco to Lisbon it lasted not less than 44 days. Five females and one male still lived on arrival, and these received the same care as the others, and the success was such that in June, 1898, these six samples received in December, 1897, had several thousands of descendants. On account of the danger to which we are exposed of some time seeing the orange groves of the south of France and the north of Africa invaded by Icerya, we believe that it will be useful to give some details as to the methods used in breeding, under the direction of M. Le Cocq. [See pp. 32-37, Bulletin 18, New Series, U. S. Dept. Agriculture, Division of Entomology.]

This method of work, which permits the handling of the Novius without touching them, has been practised in Portugal on a large scale, and thanks to this method, they were able to obtain an immense multiplication of the Australian ladybirds, but in order to facilitate the rearing still more and to obtain as great a production as possible, they constructed a large wire-gauze cage after the model already used in the United States.

In 1898, thirty-eight centers of dispersion, in Lisbon and in the suburbs, had been thus established and were in active operation. In the month of August, ninety colonies existed; in September, four hundred and eighty-seven, without counting the secondary colonies started by the orchardists themselves, who had given one another specimens of these precious insects.

The gardens and orchards, which were completely infested and almost ruined, were cleaned of the scourge as if by enchantment. The number of Icerya became practically negligible, and all treatment with insecticides was from that time entirely superfluous. In a letter addressed at this time to Mr. Howard, Mr. Le Cocq wrote as follows:

The multiplication of the Novius which you sent in November and December has been astounding.... The result exceeds everything that we could reasonably expect. The colonies of Novius are now being distributed profusely every day to many farmers and gardeners who ask for them, and you must not doubt that we recognize their just value, and appreciate the exceptional service you have rendered to Portuguese agriculture and horticulture.

However happy these results, it should not be forgotten that the Novius, in Portugal as well as elsewhere, has not been able to completely exterminate the Icerya. It keeps it from reaching the condition of a pest, but it is not able to prevent its dissemination or its slight increase. Mr. Duarte d'Oliveira, of Oporto, to whose kindness I owe certain interesting documents upon the history of Icerya in Portugal, has written me that he has recently found several colonies of this insect