35 



can species of Gonolobus, Tecomia vclulina, Bignonice, Aplulaiuh a , 

 Solamnus and other similar soft-leaved plants." Signoret (2) found 

 it on Salvia splendens and Tancana camara, and Douglas (7) speaks 

 of its injuries to cucumbers and tomatoes. Quaintance (19) reports 

 "what appears to be this insect" on Fuchsia, Pelargonium and 

 Oxalis from various parts of the Eastern United States. Britton 

 (23 and 27) lists fifty-eight food plants in Connecticut upon which 

 the insect was observed in its immature stages. It has recently been 

 recorded on violet (26). 



It is sufficient to say here that the Greenhouse Aleyrodes is a 

 very generous feeder, its food plants representing several families 

 and orders. The following food plants deserve especial emphasis 

 on account of their economic importance either as ornamentals or 

 fruit producers : Chrysanthemum, Salvia, Lantana, heliotrope, 

 geranium, Fuchsia, Coleus, Ageratum, roses (17), egg plant, bean, 

 tomato, lettuce, cucumber and melons. Tobacco, when grown in a 

 greenhouse, shows itself to be especially attractive to the insect, but 

 there is no indication that this plant grown out of doors will ever be 

 seriously troubled by it as far north as Massachusetts. I am in- 

 formed by Mr. Francis Canning, head gardener at the Massachusetts 

 Agricultural College, that in his experience the Greenhouse Aley- 

 rodes has been a serious pest of Primula obconica, a plant grown 

 quite extensively by some florists. 



ECONOMIC IMPORTANCE OF THE GREENHOUSE 



ALEYRODES. 



From an economic standpoint the most serious injury caused by 

 this species of Aleyrodes is to cucumbers and tomatoes in green- 

 houses. J. W. Douglas (7) speaks of cucumber and tomato plants 

 in England being ruined by the agency of this insect. Among the 

 more recent accounts of its injuries Britton (23 and 27) says : "For 

 eight years the most serious insect pest affecting forcing house 

 tomatoes at the station has been the " white fly," " mealy wing," or 

 plant house Aleyrodes. Were it impossible to hold the insect in 

 check, the crop each winter would be nearly a total failure." 



Within the last two years there have been several inquiries re- 

 ceived at the Hatch (Mass.) Experiment Station concerning this 

 insect, and in at least three cases serious loss to the owners resulted 



