20 



Pachytylus austrcdis Brunei, which, as Mr. Helms, of the Colonial Su- 

 gar Company, who was with me, said, were very numerous in the 15a 

 River, Fiji, and at this place often destroyed whole fields of young 

 cane. The attempt was very interesting, and I will relate the circum- 

 stances connected with it in full, as they no doubt will lead to an easy 

 way of introducing these beneficial insects so fatal to locusts into 

 other countries, and we may thereby eventually overcome the serious 

 losses that follow the invasions of locust swarms. It is proven that 

 one of these flies may be able to produce upward of 20. (KM) living mag- 

 gots, and the development is, as will be shown, astonishingly rapid in 

 a warm climate. 



I left Noumea with the living flies in glass jars upon iee. on the even- 

 ing of Mayo. L892; two days later my Hies began to die slowly, and 

 upon arrival at Sura, Fiji. May '•>, 1<S!>2. but very few were living, yet 

 the. jars were full of living maggots which were feeding somewhat upon 

 the dead Hies. It was only four days later. May !>. 1892, at Nausori, 

 that I had an opportunity of getting a lot of Pachytylus australig 

 Bruner, and by this time the remaining larva 1 had made a little growth, 

 some measuring about one-fourth of an inch in length. I made a small 

 opening in the tender skin of the locusts between the head and pro- 

 notum, and in this one or two of the maggots, according to size of 

 locusts, were placed, which disappeared almost immediately in the inte- 

 rior. Others were also placed under the slightly raised pronotum, where 

 they remained and buried themselves alone in the body. Four days 

 Inter I examined the jars containing the locusts with sod and, to my 

 surprise, two puparias of the fly were already present, while on the fol- 

 lowing day (May 14, 1892) over one hundred of the puparias were found, 

 showing that these larvae will attain their growth in from the to six 

 days. I buried the puparias about half an inch in the soil, and on 

 examining a few days later found that a colony of ants had estab- 

 lished their home with and were destroying these. Some five or six of 

 the purparias were already eaten out. All were taken up and again 

 buried separately in various places. These, as was found later, were 

 not again molested, but produced the flies in from eleven to thirteen 

 days. This will show that the whole transformation of these Hies will 

 not take more than about eighteen days. and. supposing that only a few 

 hundred of the maggots of each fly would come to maturity, it would be 

 but a short time before a large number of the locusts would be anni- 

 hilated within an area of a few miles, and by distributing the Sarcophaga 

 over tin- infested portion of the country, the locusts could no doubt be 

 destroyed within less than three months. 



Hundreds of various grasshoppers were examined in Fiji in the hope 

 of finding internal parasites, yet not in a single case could I find any. 

 nor could any dead insects be found indicating the presence of a par- 

 asite to destroy the locusts, other than such as were destroyed by 

 fungoid s. 



