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or plants received from other dealers should be examined at once and 

 rejected or at least thoroughly cleaned if found infested; this last 

 point is an important one, as the insect has undoubtedly been intro- 

 duced into new districts through the agency of auction houses, and 

 has often become extremely abundant before being recognized as a 

 new enemy. 



These precautionary measures should be supplemented by fre- 

 quent syringing with as severe a spray of water as the plants will 

 stand if any insects make their appearance. Many plants like coleus, 

 however, will not stand a syringing severe enough to wash off all the 

 insects, and so resort to an insecticide is often found necessary. 



Of the florists who use an insecticide against this insect, nearly 

 all use fir-tree oil, and all who do speak very highly of its effective- 

 ness. This substance has been tried at the Insectary, and when used 

 in the proportions recommended by its manufacturers for the Mealy 

 Bug, it has been found to be very efficient in destroying the Green- 

 house Orthezia. Its costliness is the greatest objection to its use. 



Kerosene emulsion is 'another good insecticide, and one that is 

 not as commonly used by florists as it deserves to be. Doubtless this is 

 because it is a little troublesome to prepare, but those who are willing 

 to take this trouble are well repaid. The emulsion which was found 

 to be the most efficient on the Greenhouse Orthezia in experiments 

 conducted at the Insectary was Cook's emulsion. This is made by 

 adding one pint of kerosene to a boiling solution of one-quarter 

 pound of hard soap in two quarts of water, and churning the mixture 

 thus formed until it is thoroughly emulsified, which takes about five 

 minutes ; for use, the emulsion is diluted with twice its bulk of water. 

 It must not be expected that every insect will be destroyed by one 

 application of either fir-tree oil or kerosene emulsion, and besides, 

 the eggs in the ovi-sac are not always reached. Dipping the plants 

 in the substance and holding them submerged for a few seconds ap- 

 pears to be a more successful method than spraying them. The in- 

 sects remaining on the plants left out of doors are killed by the first 

 severe frost, so no danger need be apprehended from them. (Bui. 

 28, Mass. E. S.) 



Thread Scale. This is a long narrow black scale attacking 

 palms, pandanus and many other plants in greenhouses. It has been 

 taken in Connecticut only at one greenhouse in New Haven, where it 

 was quite abundant. Little is known of its life history, and the male 

 is unknown. The female shell is from 2 to 3 mm. long, and about 

 eight times as long as broad, and more or less curved. The writer has 

 had no experience in combating this scale, but the same treatment 

 used for other greenhouse scales will doubtless hold it in check. 



Chaff Scale. This is common on various greenhouse plants, 

 especially orange and lemon. It is oval in shape, with the molted 

 skin at one end, and is light yellow in color. It is usually found in 

 clusters. The common sprays used for greenhouse scales seem to be 

 effective against this species. 



Soft Scale. It is an oval, slightly convex brown species com- 

 monly found on citrus trees, oleanders and many other plants in 



