1.1^2 THE CANADIAN ENTOMOLOGIST 



sticky secretion. In the same paper will be found a list of flower visitors not 

 caught and summaries of other papers dealing with Apocynum insect visitors. 



A REVISION OF SYRPHUS SPECIES BELONGINCx TO THE 



RIBESII GROUP (DIPT.) 



,V 



BY C. HOWARD CURRAN, 



Orillia, Ontario.' 

 With the recognition of three European species of Syrphus in Canada,- 

 viz. S. vitripcnnis Meig., nitidicollis Meig., and ochrostoiinis Zett., and the dis- 

 covery of some species which are evidently undescribed, the need of a revise'd^ 

 synopsis of those species with the disc of the thoracal squamse hairy seems 

 desirable. Several of the species are very closely related and often separable 

 only after considerable study. Without going into minute detail, the author 

 hopes, by means of the present paper, to render the identification of the various 

 species less difficult than it is at present owing to the scattered nature of the 

 descriptions. *' 



The chief characteristics of the members of this group lie in the presence 

 of three principal yellow or reddish yellow abdominal bands, the first of which 

 is interrupted, the two following entire, and reaching the lateral margins of the 

 segments, except in 5. opinator O.S. Nine species have the squamae pilose above 

 and eight bare, although if S. insoUtus Osb., which belongs to this group, is- 

 included, nine species belong to each section. 



Syrphus xantliostomus Will., recognized from S. grossitla/iac by its 

 yellow antennae and yellow scutellar pile and S. iiisolitiis, which has a black face,,, 

 are not dealt with in this paper. 



Table op Species. ,, 



1. Disc of thoracal squamae hairy • 2 



Disc of thoracal squamae pilose 14 



2. Eyes pilose c^ $ torvus O.S. 



Eyes bare 3 



3. Hind femora of female black at base $ vitripennis Mg. 



Hind femora of female yellow at base 4 



4. Second and third bands do not reach abdominal margins. (^ $ opinator O.S. 

 Second and third bands reach margins 5 



5. Abdominal bands extend over margins in their full width ; legs bright 



yellow except dark band on hind femora; middle basitarsi with all 



yellow small spines below. ll-12mm ... J^J knabi Shannora 



Bands usually attenuated laterally ; middle basitarsi with black spineS' 

 below . 6 



6. Hind femora black at base 11 



Hind femora yellow at base 7 



7. Femora wholly yellow in both sexes ; antennae reddish ; cheeks often 



narrowly blackish below the eyes c^ $ protritus O.S~ 



Femora not wholly yellow ; antennae chiefly blackish 8 



8. Abdomen with the sides strongly reflexed downwards ; apical segments! 



all visible from above $ transversalis n. sp. 



