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thickly colonize the tender terminal shoots, the two species being 
often intermixed. 
Length about one sixteenth Fig. 30. Green Chrysanthemum A phis, Aphis rufomaculata, 
inch. winged viviparous female. Length about one sixteenth inch. 
The melon aphis ( Aphis gossypii Glov.), a species which varies 
greatly in color—from pale to dark green or nearly black—is 
quite common in conservatories, attacking such plants as Althcca 
and Easter lily. 
Two species ( Macrosiphuni rosce Linn, and Myzus rosarum 
Ivalt.) are commonly found attacking the rose in greenhouses. Both 
are greenish in color and gregarious on the terminal shoots. They 
are practically monophagous, the rose being their usual food plant. 
Carnations often become badly infested with a green plant-louse 
(Myzus persiccc Su\z.—Rhopalosiphum dianthi Schrank). Its 
habits are like those of the species previously mentioned as to colo¬ 
nizing the terminal shoots, but it is decidedly different from them 
in its feeding habits, since it can live and multiply on a great variety 
of vegetation. The flowering and ornamental plants which have 
been found most susceptible to its injury are carnation, asparagus 
fern (Asparagus pliimosus ), Cineraria, marigold, Primula, and 
Vinca. It does not limit itself to greenhouse plants, but is also a 
fruit-tree and vegetable pest of considerable importance, peach, 
plum, cabbage, turnip, radish, and spinach being liable to injury 
by it. 
Another plant-louse which feeds on a variety of plants but 
which seems to be strictly a greenhouse species, is Myzus vincce 
Gill.* It is of a greenish color, with blackish horseshoe markings 
on the abdomen, which are quite characteristic in the wingless 
*This species is probably the same as the European Macrosiphuni circum- 
flexuni Buckton, as it agrees with the description and figures of that species 
and has the same habits. However, until their identity has been positively 
determined by actual comparison of our species with the European one it 
seems best to retain the name given by Gillette. 
