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large degree and induced the Government to go further and see 

 what could be done to control the ravages of the melon-fly. In 

 this way the writer was engaged in July, 1915, to investigate the 

 parasitism of the melon-fly and obtain whatever natural enemies 

 could be discovered. 



Before going on to the detailed account of the expedition, it 

 should be stated that when the search for melon-fly parasites was 

 begun, our knowledge of the fly outside of Hawaii was very 

 limited, consisting almost wholly of the probable distribution of 

 the fly gained from the meagre records of Compere and Muir 

 and the publications of the Imperial Entomologist of India. 

 Nothing positive was known of parasites, although Muir's ac- 

 counts of the relative scarcity of the fly in certain localities gave 

 a measure of confidence to the assumption that parasites existed. 



In regard of the facilities offered by the Government labora- 

 tories in India, it was considered that it would be the country to 

 work first, and on 23rd July I set out with the intention of 

 going directly to Pusa in India. When I reached ^lanila, how- 

 ever, I went up to Los Baiios to have a conference with Muir, 

 and it was largely on his recommendation that I decided to work 

 first around Singapore. 



While at Hongkong, 17-20th August, on my v/ay to Singapore, 

 I made a short trip up the river to Macao, w!here Muir and Ker- 

 shaw had worked considerably, to determine its suitability as a 

 breeding station on my probable return with parasites. 



Leaving Hongkong on the 20th, I arrived at Singapore on the 

 26th, located a supply of infested fruit in some Chinese vegetable 

 gardens, and set up my laboratory in a room over the hotel 

 garage. Here I worked over a month, rearing melon-flies out of 

 cucumbers and a few Momordicas and Luff as. At the end of a 

 week on opening some of the puparia, I found a single female 

 Opiiis, and shortly after two males, and felt encouraged to go on. 

 However, although more than 6,000 flies were reared, no further 

 parasites vv^ere obtained, and I decided to continue on my way 

 to India. I attribute the meagre results obtained in Singapore 

 to the character of the fruit used, and the manner of its cultiva- 

 tion. The only cultivated cucurbit to be obtained in any quan- 

 tity is the cucumber, which is produced by Chinese market gar- 

 deners under conditions which are very favorable to mould — the 

 ground where these gardens are is low, and it is the custom of 

 the Chinese to wet down the beds three or four times a day with 

 liquid manures. I think if wild Momordicas could have been 

 obtained, the parasites would have been more abundant, but un- 

 der the conditions described, the parasites have little chance to 

 multiply. 



The method used to ascertain what parasitism existed was very 

 simple. Infested fruit was placed in cages on sand, and as soon 

 as the maggots had emerged and pupated, the sand was screened 

 to separate the puparia, which were then placed in shell vials. 



