334 NEW YORK STATE MUSEUM 



United States. It is known to be present in a number of widely sepa- 

 rated localities in New York state, and it will probably be found in 

 greater or less numbers wherever greenhouse plants have been grown for 

 some years. * 



Food plants. This pest is able to subsist on a number of different 

 plants. Prof. Comstock has studied it on acacia, magnolia, oleander, 

 maple, yucca, plum, cherry, currant and the china-tree, M e 1 i a a z e d - 

 arach, in CaHfornia and on ivy at Ithaca (N. Y.) He also found it 

 on grass and clover growing in pots with infested trees and on lemons 

 from the Mediterranean and from California. Prof. Morgan states that 

 it is very abundant on the " china-tree" in Louisiana. It is recorded as 

 a pest of the olive in countries where that tree grows. Prof. Johnson 

 states that it is particularly destructive in Maryland to Asparagus 

 plumosus, the so-called lace fern. D. VV. Coquillett records it in 

 California on the following additional plants : lilac, arbor vitae, century 

 plant or aloe, oak, Quercus agrifolia, and nightshade, S o 1 a n u m 

 d o u g 1 a s i i . It has also been collected in Albany greenhouses on 

 Areca lutescens, Cyperus, Kentia belmoreana and 

 Strelitzia reginae. 



Natural enemies. Prof. Morgan reports rearing a hymenopterous 

 parasite from this scale insect, and Mr Coquillett states that the imported 

 Australian lady bug, Rhizobius debilis Blackb., feeds on this 

 species in California. 



Preventives and remedies. It is comparatively easy to control 



this insect in New York state, since it can not live outdoors. It can be 



kept in check by spraying or washing the infested plants with whale oil 



soap solution (i pound to about 5 gallons), kerosene emulsion (diluted 



with 12 parts of water, see p. 339) or an ivory soap solution (a 5 cent 



cake of the latter to 8 gallons of water). These substances will hardly 



do more than keep this insect in check, and repeated applications will be 



necessary. It will be much more satisfactory, as a rule, to clean the 



greenhouse thoroughly in the summer and then stock up with clean 



plants. 



Bibliography 



The more important articles treating of this species in America are 



listed below. No attempt has been made to look up references in foreign 



publications, as the list, at best, would be very incomplete. 



Signoret, Victor. Essai sur les Cochenilles ou Gallinsectes. 1868. 

 p. 96-97 (description) 100-3 (food plants, description, as A. nerii). 



