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1387, a specimen of a handsome species of the Mymarid genus Alaptus 
which he had reared from orange leaves infested with the so-called 
Yellow Scale from San Gabriel. This he at first supposed to be a par- 
asite of the scale insect, but as he afterwards reared a large series of 
the same species from the little eggs of a Psocid — Cwcilius aurantia- 
cus — he concluded that his first specimen probably issued from some 
unnoticed Psocid egg among the scales on the leaves. He is, without 
much doubt, correct in his conclusion, and the species is mentioned 
here simply to warn other investigators against falling into the same 
error. 
The true parasites are as follows : 
(1) Aspidiotiphagus citrinus Craw 
(2) Coccophagus aurantii n. sp. 
(3) Coccophagus lunulatus n. sp. 
(4) Aphelinus diaspidis Howard, 
(5) Signiphora californica n. sp. 
(6) Aphycus immaculatus n. sp. 
Owing to the occurrence throughout this article of the names "Bed 
Scale," " Yellow Scale," u Aspidiotus aurantii, typical form," and 
u Aspidiotus aurantii var. citrinus," it will be necessary to explain that 
they all refer to the same species, which exists in California in two dif- 
ferent forms. The typical Aspidiotus aurantii, or Red Scale, is the 
form described by Maskell from New Zealand, and which also occurs 
in Australia and in the Mediterranean countries. It was studied by 
Prof. Oomstock in California, in 1880, and described and figured in his 
report for that year. The name " Yellow Scale " is in common use in 
California, and refers to a light brownish-yellow variety of the Red 
Scale which occurs principally in the San Gabriel Valley in California, 
but which is also found in all other orange- growing portions of the 
State. This variety differs not only in color, but the dorsal and ventral 
scales seem to be more firmly cemented together than with the typical 
Red Scale, and it occurs, moreover, only upon the leaves and fruit, 
never upon the bark, while the typical Red Scale occurs very abun- 
dantly upon the bark as well as upon the leaves and fruit. The typical 
Red Scale, moreover, seems to be oviparous, while the Yellow Scale is 
viviparous. The Yellow Scale is mentioned in some California publi- 
cations as Aspidiotus citrinus Coquillett, and Mr. Craw is of the opin- 
ion that it is a distinct species and was imported independently from 
Japan into the San Gabriel Valley. The name Aspidiotus citrinus 
Coquillett was sent to Prof. Riley with a MS. description, bat from his 
own careful study in California and correspondence with Mr. Coquillett, 
Prof. Riley concluded that the structural differences between the two 
forms are not constant, and that citrinus can only be considered as a 
variety. 
