October, ’24] 
armitage: citrophilus mealybug 
555 
in the orchards of the coast counties where it has periodically caused 
considerable injury to this host. Baker’s mealybug (. Pseudococcus 
maritimus Ehrh.) and the Longtailed mealybug (. Pseudococcus longis- 
'pinus Targ.) have also been of common occurrence on citrus over the 
same area but can never be said to have been of any real economic im¬ 
portance. With the finding of a new species, (1) the Citrophilus mealy¬ 
bug ( Pseudococcus gahani Green) at Uplands, San Bernardino County, 
in 1913, there was added to this group a member which has given evi¬ 
dence of being as serious a pest as the citrus mealybug, if not more so, 
and is now recognized as one of the major insect pests attacking citrus 
in Southern California. 
The finding of this species at that time was particularly alarming to 
the citrus growers of the interior valleys as it had been previously sup¬ 
posed that this well-known pest of citrus in the coastal areas could not 
exist under their hot, dry climatic conditions. While the original out¬ 
breaks were rather severe in both San Bernardino and Riverside Coun¬ 
ties, the two principal interior citrus producing counties in the Southern 
part of the State, recent developments have indicated that these climatic 
factors have a marked restricting influence in those areas, and while its 
spread has continued no serious infestations have been experienced since 
1919. The coast areas however, seem as well adapted to this as to the 
other established species. Its spread, after once becoming established 
has been rapid with many serious outbreaks. 
The Citrophilus mealybug is a rather omnivorous feeder, resembling 
Pseudococcus citri in this respect, and aside from citrus, attacks a wide 
range of host plants including many ornamentals as well as fruit trees. 
In fact, while records are rather indefinite on this subject, this pest was 
without doubt introduced into the citrus orchards of Southern California 
on ornamentals either from the vicinity of Los Angeles or from the San 
Francisco Bay region in both of which areas there is evidence of its 
occurrence prior to 1913. 
General Descriptions 
While this species might, from an external examination in the more 
immature stages be mistaken for the citrus mealybug, the adult female 
has a distinctive form and appearance which easily distinguishes it 
from the other species attacking citrus. 
Green (3) has given the following very accurate and characteristic 
description: “adult female thickly coated with greyish-white mealy 
secretion, which is thinner in the folds of the segments and in the de- 
