104 
The work done en hornfly control embraced an investigation of the 
natural agencies limiting the abundance of dung flies in Australia by 
Mr. J. r. iJlingworth, formerly Professor of Entomology at the Uni- 
versity of Hawaii and more recently Government Sugar Entomologist 
in Queensland, and in Southwest United States and Mexico by Mr. 
Herbert T. Osborn, Assistant Entomologist a-t the H. S. P. A. Experi- 
ment Station. On the basis of these investigations shipments were made 
of the most promising species of parasites, predators and scavengers 
which have been released in suitable localities on Oahu^ Hawaii and 
Maui. Four consignments were received from Mr. Illingworth, six from 
Mr. Osborn, consisting for the most part of various species of dung 
rollers or tumblebugs {Copriid beetles). More stress has been put upon 
establishing copriphagous agents than upon parasites because it is be- 
lieved the destruction of the dung is the most important element of the 
problem at the present time. If the number of flies could be reduced 
fifty per cent by destroying their breeding places, the action of para- 
sites and predators would soon be appreciated. A detailed report on 
the progress of this work up to the middle of November appeared in . 
the October Forester. Since then two additional consignments of ma- 
terial have been received from Mr. Osborn. 
The pineapple insectr investigations had their origin in an outbreak 
of fruit beetles at the time of harvesting the crop and have been con- 
tinued since that trouble disappeared, on account of the appearance of 
red spider in the fields on the island of Oahu. Control methods are 
being studied not only for the red-spider but also for the mealybug and 
scale which are believed to be responsible to some extent for the out- 
break of the fruit beetle and heart rot. 
A parasite of the fern weevil, discovered by Mr. Pemberton in Aus- 
tralia, has been introduced and established in these islands and promises 
to furnish an effective control upon the weevil which threatened the 
destruction of part of the ground cover in our forests. The introduction 
was noted in the July Forester. 
Assistance was given to the Federal Entomologist in Hawaii in in- 
troducing and colonizing additional parasites of the bean weevils. A 
detailed account of this work appears in the September Forester, and 
it is gratifying to be able to report the establishment of at least one 
of these parasites already. The establishment of one of the pupal 
parasites of the fruit fly introduced by Dr. Silvestri in 1914 is also 
noted. 
The publications from this office during the year, in addition to those 
already referred to, have been — 
The Fern Weevil {^yafirins fiilrifarRin Pa.9c.) 
■ Hawaiian Forester, V. XVIII. 5, pp. 101-114, PI. 1. May. 
Notes on Immigrant Coleoptera (in the press). Also, a paper on 
the Insect Problems of the Pineapple Industry was prepared and 
read at the Annual Conference of Field Workers held by the Ha- 
waiian Pineapple Growers' Association, November 17, 18 and 19, 
Respectfully submitted, 
D. T. FULLAWAY, 
' Entomologist. 
TABULATION SHOWING THE LIBERATION OF BENEFICIAL IN- 
SECTS 1921 
Oahu Kauai Molokai Maui Hawaii Total 
Fruit fly Parasites* 
Galesus silvestri 6,550 350 .... 6,900 
Diachasma tryoni 12,322 300 700 .. .. 13,322 
Tetrastichus giffardianus 22,250 500 1,900 .... 24,650 
