Sphaerophoria. 341 



sliape of a Si/rphus-iavya. ; it is corrugated above, the dermis is finely 

 chagreened, and there are very small bristles on the dorsum and at 

 the sides, arranged quite as in Syrphus; below there are slight, trans- 

 verse swellings; the posterior spiracular process is not quite short, 

 black, with a longitudinal dividing furrow above and below, and the 

 apex cleft with the points a little diverging. The larva is light green 

 with two whitish, longitudinal dorsal stripes (Bouché describes it as 

 grey with two whitish stripes, Zetterstedt as green). The length is 

 8 mm or more. The pupa is broad and rounded in front, attenuated 

 behind and thus drop-like; the spiracular process as in the larva; it 

 is green during the first part of the development, later the imago 

 shines through, and the empty puparium is whitish; the length is 

 6 mm. 



The larvæ are aphidiphagous; they evidently hibernate, as my 

 larvæ found in flood refuse in late autumn and early spring show; 

 but as I also found a larva on '^li, developing on ^'V?, and as Zetter- 

 stedt mentions it developing as late as ^^Is, and the above recorded 

 pupa developed on ^^/s I am inclined to think that there are, or may 

 be, more than one brood in the year. At the pupation the larva 

 attaches itself by the posterior part to a leaf or stalk, and in this 

 condition the pupa remains. 



The species of Sphaerophoria are characteristic and easily re- 

 cognizable flies ; they occur on various localities, not rarely near water 

 and also near the shore, on various flowers. The genus goes high 

 towards the north, one species, our scripta {strigata) occurring in 

 Greenland. — The species have been very troubling on account of 

 their strongly varying or tending to produce local races, and a very 

 large number of varieties, especially of scripta and menthastri, have 

 been described as separate species (each of these species have been 

 described about as 14 species). Already Malm suggested in 1860 that 

 the species should be much reduced, and Kowarz in 1885 reduced 

 eight species to the two well known scripta and menthastri. Finally 

 Verrall undertook a radical reduction, and I quite foUow him. The 

 characters which were given for the many species were only taken 

 from variations in the abdominal markings and the colour of the legs, 

 as it is only with regard to these that the species vary, and many 

 other Syrphids are more or less varying in this respect. The two 

 species specially in question, scripta and menthastri^ are in spite of 

 their varying well recognizable as good species, showing several con- 

 stant plastic characters proving them to be only two, and two well 

 distinguished, species. 



The number of species in the palæarctic region is now about 10, 

 and of these only 4 are European, all also occurring in Denmark. 



