1 10 Oithonhapha bracliyceia. 



observed copulation ; tlio copulation ahvays took place about 8 o'clock 

 in the morning, before the insects had begun to tly. The male was 

 sitting, while tiie feraale hung suspended. — The species are distributed 

 all over the world, they seem to a certain degree to abound in moun- 

 tain districts, going rather high, certainly on account of the forms of 

 ruminants iiving liere; the males then sometimes may be seen hovering 

 on high mountain tops. This distribution is the cause that there are 

 not many species occuring in Demnark, while there are more both 

 north and south of us. 



Of the genus 129 palæarctic species are known, of whicli 14 

 occur in Denmark. 



TahJe of Species. 

 Males. 



1. Eyes hairy 2. 



— Eyes bare 9. 



2. Eye-facets equal or only slightly different in size 3. 



— Eye-facets of different sizes, the dividing line sharp 6. 



3. Second joint of palpi small, not swollen; eye-facets 



nearly equal, eyes with Ihree bands 1. montanus. 



— Second joint of palpi more or less thickened or swollen 4-. 



4. Eye-facets nearly equal, eyes with three bands 5. 



— Eye-facets distinctly of different sizes, eyes with two 



bands and one rudimentary 4. MiihJfeldi. 



o. Head low, eye-suture not much longer than (the frontal 



triangle 3. luridus. 



— Eye suture about twice as long as the frontal triangle . . 2. tropicm. 



6. Upper eye-margin with long, erect hairs G. plehejus. 



— Upper eye-margin without erect hairs 7. 



7. Femora black, or only the extreme tips yellow 8. 



— Femora yellow, only more or less black at the base. . 8. fulvtts. 



8. Head large, eyes without bands, or with one dark 

 band ; second joint of palpi cylindrical ; anteiior branch 



of cubital vein nearly ahvays with a veinlet 7. rustietts. 



— Eyes with two bands and one rudimentary ; second 

 joint of palpi swollen; dividing line between the eye- 

 facets not very sharp 5. sohtitialis. 



9. Eye-facets of equal sizes 9. hovinus. 



— Eye-facets of different sizes 10. 



10. Upper eye-margin without erect hairs 11. 



— Upper eye-margin with erect hairs 13. 



11. Small eye-facets sharply separated from the larger, 

 ascending along the eye-margin to the ocellar tubercle 



as a band of nearly equal breadth 12. autumnalis. 



— Small eye-facets scarcely so sharply separated from 

 the larger, ascending along the eye-margin in a band 

 upwards decreasing in breadth 12. 



12. Large species; eyes without bands 10. sudeticus. 



