a fully maturedinsect. It then ceases to feed, 
falls to the ground, and enters the ground 
exceedingly small natural cavity and shapes 
or just a little longer than the insect itself. 
THE PEAR THRIPS. 9 
incision, of the head with its bright red eyes. Little by little, and 
swaying backward and forward, the larva forces itself out until about 
one-half of the body is exposed, when first the antenneze and then 
one by one the pairs of legs are made free from their resting position 
against the body. Swaying backward and forward, with legs and 
antenne waving frantically about, the insect pushes out of the egg 
cavity almost to its full length, whereupon, leaning forward it eagerly 
takes a hold with its newly formed feet, and, with a final effort, pulls 
itself free and walks rapidly away. From four to ten minutes are 
required for the insect to free itself from the egg. The young insect 
is almost transparent and the green chlorophyll particles taken into 
the stomach can be seen through the body wall. Growth is rapid 
from the beginning. 
A very decided change takes place during the second larval stage 
(fig. 4). In about three weeks the insect 
reaches a size often larger than that of the (ii \\ 
_by some crack or wormhole. It goes down 
- from 3 to 10 inches, according to the structure 
and condition of the soil, the usual depth 
being about 4 inches. Upon reaching a 
secure depth, the larva hollows out for itself 
a tiny spherical or oblong cell or it finds an 
this for its convenience. The completed 
chamber has a hard, smooth inner wall, 
and it is about one-twelfth of an inch long, 
The insect here spends the greater portion fig. 5.—The pear thrips (Euthrips 
of its life. It remains for several months = ?¥?!): nymph or pupa. Much en- 
. : larged (original). 
a quiescent, non-food-taking larva. Later 
the pupal changes are undergone, and lastly the adult insect appears 
5 ron) ) v 
before it issues forth to the tree. Larve collected from the ground 
on August 28 were active, and, strange to say, green chlorophyll 
matter, undigested food, which had been taken into the stomach 
several months before, was still present in their bodies. The insects 
are scattered through the soil from near the trunk to several feet 
from the tree. 
THE NYMPH OR PUPA. 
The writer has not been able to determine how long the nymph 
stage (fig. 5) lasts, but it evidently extends over several weeks. 
Nymphs in all stages of development were collected during May and 
at intervals until the following February, but they are most common 
during December, January, and February. The writer has gathered 
