Geometridae 
Genus EOIS Hubner 
(i) Eois ptelearia Riley. (The Herbarium Moth.) 
The moth which is the subject of consideration is interesting 
because of the fact that in recent years it has become known as a 
destructive herbarium pest. The larvse attack the flowers, to 
Fig. 199 .—Eois ptelearia. a , larva, from side; b, do., from 
above; c, side view of abdominal segment; d, tubercle of same; e, 
pupa;/", cremaster; g, abdominal projection. All figures greatly 
enlarged. (After C. V. Riley, “ Insect Life,” Vol. IV, p. 109.) 
some extent the leaves, and also to a less extent the hard fruits 
and seeds of specimens collected in the Southwestern States 
and in Mexico. Their ravages were first detected at the 
United States National Museum in the year 1890. Strangely 
enough, they show no appetite for species belonging to the flora 
of the Eastern and Northern States. It is believed that the insect 
is native to the region the plants of which it devours, but thus 
far no entomologist has reported its occurrence in the section of 
country from which it is supposed to come. The damage it 
is able to inflict upon specimens is very great, because of the 
very rapid multiplication of individuals which takes place. 
An exceedingly interesting account of the insect and its 
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