S YRPHIDAE 



By Frank M. Hull, Texas State Experiment Station, College 

 Station, Texas, U.S.A. 



(With 2 Text-figures.) 



The insular distribution of Syrphid flies is nowhere of greater interest than in 

 the Bast Indian and South Pacific regions, and I wish to express my thanks to 

 Mr. P. A. Buxton, through whom I am able to present the following studies of 

 the Samoan S3rrphid fauna. An analysis of material from this region is 

 rendered the more interesting in view of the publication of certain dipterological 

 studies of the Fiji islands by the late Dr. Mario Bezzi {Diptera Brachycera and 

 Athericem of the Fiji Islands, 1928). The Samoan Syrphids show a marked 

 similarity to that of the Fijian group. Eleven species, belonging to ten genera, 

 were recorded from Fiji, and the present pa.per lists ten species (one hundred and 

 forty-five specimens), representing nine genera ; eight of the Samoan species 

 were found also in Fiji. Moreover, in both archipelagos an unusually high 

 percentage of species fall within the subfamily Syrphinae. It is certainly 

 peculiar that the island regions, Samoa, Fiji, and New Zealand, as far as present 

 records show, should contain markedly high Syrphine components, in contrast 

 to especially low ones in the case of such islands as Sumatra, Borneo, Java and 

 Celebes. The average for the latter region is about 18 per cent., and for the 

 former as high as 66 per cent., with the highest of all represented by 70 per cent, 

 in Samoa. Finally, it may be remarked that Eristalinae and Milesiinae seem 

 to predominate farther to the north-west. The Samoan Syrphids are of Malayan 

 origin, five of the ten species occurring also on the Asiatic mainland. 



Syrphinae. 



1. Melanostoma univittatum Wied. 



Sixty-two specimens from the following localities : 



Upolu : numerous examples from Apia, Afiamalu, Vaea, Vailima, Malolo- 



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