ENTOMOLOGY 257 



these soap applications. (New Series I No. 2 Cornell Reading 

 Course for Farmers' Wives.) 



The Greenhouse Orthezia. This insect is a tropical insect some- 

 what closely allied to the common mealy bugs familiar to every 

 florist. It has its mouth part* formed for piercing and sucking, and 

 obtains its nourishment by imbibing the plant sap, like all other 

 species of the family to which it belongs. The young are very small, 

 and would hardly be discerned on a plant were it not for the presence 

 of snow white plates of waxy matter which occur on the back and 

 sides, and which contrast strongly with the darker background of the 

 body. The adult females are about the size of the head of a pin and 

 resemble the young in appearance, but bear in addition to the white 

 plates on the back and sides a somewhat cylindrical sac of the same 

 substance, which projects for some distance behind the insect and in 

 which the eggs are carried. At the posterior end of this sac is an 

 opening through which the young crawl soon after hatching from 

 the egg. The young are then quite lively, and scatter well over the 

 stem and underside of the leaves of the plant. As they grow older 

 they become sluggish, but always retain their power of locomotion. 

 The mature males have a single pair of wings, and, being very 

 minute and also rare, are seldom noticed. 



The Greenhouse Orthezia has not as wide a range of food plants 

 as the Mealy Bug, but it attacks a greater variety of plants than 

 most florists are aware of. It has been found on lantana, verbena, 

 lemon verbena, coleus, salvia, libonia, peristrophe, ipomoea, agera- 

 tum, cineraria, eupatorium, stevia, chrysanthemum, pilea, segar 

 plant, oxalis, pelargonium, abutilon, malvaviscus, fuchsia, heliotrope, 

 periwinkle, potato, mint, white violet, and forget-me-not. In trop- 

 ical countries it is reported as infesting citrus plants. On all in the 

 list as far as chrysanthemum, when allowed to increase without mo- 

 lestation in the insectary greenhouse, it became sufficiently injurious 

 to cause the death of the plant. 



Coleus appears to be the most favorable plant for its increase, 

 and it is of its injuries to this plant, especially to the variety known 

 as verschaffeltii, that florists most frequently complain. During the 

 winter it is very destructive to the coleus cuttings in the green- 

 houses, and, if at all numerous on the young plants when they are 

 set out in spring, it is almost sure to increase in a short time to such 

 prodigious numbers that it kills or greatly weakens the plants before 

 frost in the fall. (Bui. 28 Mass. E. S.) 



As the plants which this pest infests are mostly tender annuals, 

 it is difficult to destroy the insects with insecticides without injuring 

 the plants. This makes preventive measures of more importance 

 to hold the insects in check than remedial ones. Most of the plants 

 are used for bedding purposes, and as these are nearly all placed 

 out of doors in the summer, not many insects would get into the 

 houses to breed and cause trouble in the winter if the plants brought 

 in from outside and the few which may have been kept in the houses 

 during the summer were thoroughly cleaned in the fall. Cuttings 

 for stock should only be made from uninfeeted plants, and cuttings 



