49 



years, the volume on insects, promised years ago by 

 those in charge of the Geological Survey of the state 

 ifiay be forthcoming, if not in the publications of that 

 survey, in some form which shall be provided 

 hereafter. 



The family Syrphidae is com[)osed of a variety of 

 species, some are shining while others are clothed 

 with dense pile ; most of them are marked with 

 yellow but some are uniforndy black or blue. How- 

 ever variable they may be in other particulars they 

 most all agree and are characterized, in having what 

 is known as the spurious vein between three and five 

 of the regular series. 



With one or two exceptions, none of the species 

 are known to be injurious, in the sense that the term 

 is used in economic entomology, but on the othe)- 

 hand, many of them are beneficial as the larvae in 

 many cases feed upon plant lice, and in others act as 

 scavengers in removing- oidure and decomposing 

 animal remains. Some species also live in the nests 

 of anls and humble bees and in some cases at least are 

 thought to be parasitic. 



Many instances of protective resemblance may be 

 cited in the family, thus in the single genus Eristalis 

 we find species which closely resemble bees of the 

 genera Apis, Bombus and Osmia, while other genera 

 contain species which resemble Vespa and many 

 other wasps. It would seem that we are safe in call- 

 ing this resemblance protective since the species re- 

 sembled is. so far as I am able to state, one that is well 

 fitted for protecting itself. (3ne is more strongly con- 

 vinced if he observes some of the species on the wing. 

 Thus, Spilomyia longicornis and others, resemble so 

 closely our connnon Vespa germanica. that it takes the 

 closest observation on the part of the collector to dis 

 tinguish between them. Both species have the yellow, 

 transverse bands on the abdomen, they fly in the same 



