ENTOMOLOGY AND PLANT QUARANTINE 
75 
southern areas; (3) detecting the presence of screwworras in advance of the 
gradual spread of the pest in the Southeastern States; (4) enlisting the efforts 
of stockmen in stamping out localized infestations in advance of the regular 
spread of the pest in the Southeastern States and in stockyards; (5) effectively 
reducing cases in the overwintering areas so as to reduce the numher of parent 
flies in the spring and to retard development of large populations of screw- 
worms ; and (6) preventing a build-up of screw worms in shear cuts in the 
sheep- and goat-breeding area of Texas and in southeastern New Mexico. 
INSECT IDENTIFICATION 
During the year 48,999 dilferent lots of material were received for identifica- 
tion, and the number of determinations made totaled 77,856, an increase of more 
than 20,000 over the number reported for 1936. Sixty-eight percent of the 
identifications were for interceptions by the Division of Foreign Plant Quaran- 
tines, 16 percent related to material submitted by the remaining divisions of the 
Bureau and other Federal agencies, and the balance applied to specimens re- 
ceived from State experiment stations, agricultural colleges, and other institu- 
tions in the United States and its territorial possessions and from numerous 
individuals, both in this country and abroad. At the end of the year 6,277 lots 
remained unfinished, this number being slightly higher than the corresponding 
figure for 1936. Assistance has also been given to numerous taxonomic spe- 
cialists, both American and foreign, attached to educational institutions, mu- 
seums, and experiment stations, in connection with the solution of problems in 
insect classification. 
During the brief periods not required for identification work, investigations 
were conducted on a variety of taxonomic problems with the object of improving 
the classification of difllcult economic groups that have been in a state of 
confusion. Forty-three manuscripts were completed and submitted for publi- 
cation, 24 of which were published. Most of these papers are very short, but 
a few that are comprehensive treatments of larger groups present the results 
of studies that have been under w^ay for several years and include, for example, 
a revision of the horseflies of the subfamily Tabaninae and one covering the 
mites belonging to the subfamily Tarsoneminae. 
Studies, unavoidably intermittent because of the demands for identifications,, 
have been begun on the classification of various economic groups. Following are 
some of the larger of these undertakings: Classification of the white grubs 
]-evision of the wood-boring beetles of the genus Clirysol)othris ; revision of the- 
blowflies: revision of the fruitflies of the genus Anastrepha; revision of the 
moths of the family Gelechiidae; monograph of the moths of the family Tor- 
tricidae; revision of the moths of the family Oecophoridae ; classification of the 
New World moths belonging to the Phycitinae ; generic classification of the fleas ; 
revision of the bee genus Osmia; studies on the classification of chiggers : revi- 
sion of the parasitic wasps of the genus Ophion; generic classification of the 
leafhoppers of the family Cicadellidae ; revision .of the aphids belonging to the 
genus Myzus; studies on scale insects of the genus Asterolecanium ; and a 
morphological study of the male genitalia of the Hymenoptera. 
FOREIGN PARASITE INTRODUCTION 
Particular attention was given to the collection and importation of natural 
enemies of the oriental fruit moth, the pine shoot moth (Rhyacionia huoUana 
Schiff.), the larch casebearer, the hessian fly, the European corn borer, the pea 
weevil, the vetch bruchid, and the lima bean pod borer. The importations of 
fruitfly parasites into Hawaii and of parasites to be used against a variety of 
pests in Puerto Rico, both under special funds, have been completed. 
PARASITES OF FRUIT INSECTS 
Shipments of cocoons and adults of oriental fruit moth parasites from Japan 
and Chosen during the fall of 1936 totaled 19,335, representing 16 species. These 
are the same as have been imported in preceding years. During the spring of 
1937 a total of 102,166 infested peach twigs were collected in Japan and 121,085 
in Chosen, and the parasites contained in them, numbering 41,489, were for- 
warded during June. 
