115 
*Meadowlark {Sturnelta magna). 
Orchard oriole {Icterus spurius) . 
Baltimore oriole {Icterus galbula). 
*Crow blackbird {Quiscalus quiscula seneus). 
^ Great-tailed grackle ( Megaquiscalus major viacrourus) . 
Western lark sparrow {Chondestes grammacus strigatus). 
Chipping sparrow {Spizella socialis). 
Field sparrow {Spizella pusilla) . 
*Towhee {Pipilo erythrophthalmus) . 
"^Cardinal {Cardinalis cardinalis). 
Blue grosbeak {Guiraca cxrulea). 
Indigo bunting ( Cyanospiza cyanea ) . 
Painted 'bunting ( Cyanospiza ciris ) . 
Summer tanager {Piranga rubra). 
Northern yellow-throat {Geothylpis trichas hrachidactyla) . 
Yellow-breasted chat ( Icteria virens) . 
* Mockingbird {Mhnus polyglottos). 
* Catbird {Galeoscoptes carolinensis) . 
* Brown thrasher {Toxostoma rufum). 
Carolina wren {Thryothorus ludovicianus) . 
Texas wren ( Thryomanes bewichii cryptus). 
Tufted titmouse {Bseolophus bicolor). 
Blue-gray gnatcatcher {Polioptila cserulea). 
* Robin {Merula migratoria) (in early spring and late fall). 
* Bluebird ( Sia lia si a lis ) . 
PARASITES. 
Under this head we have to consider a very important factor in the 
natural control of the bollworm. There are two stages in the life his- 
tory of the bollworm when the 
destructive work of parasites 
is most effective. These are 
the egg and the young larva, 
two stages which are passed 
before the bollworm has done 
the greater part of its dam- 
age. As the method of at- 
tack is so different in each 
case it will be well to consider 
them separately. 
PARASITES OF THE EGG. 
There are two small spe- 
cies of Hymenoptera which 
are parasitic on bollworm 
eggs, but one of them is of very rare occurrence and has but little 
economic significance. The second, Tricliogramma pretiosa Riley, is 
extremely abundant and of great vakie (fig. 20). The eggs of the 
Fig. 20.— Trichogramma pretiosa (from Riley). 
