Wiedemann's insect has since been formed into the genus 

 Rhamphidia by Meigen, and it differs essentially from the 

 species before us in having 16-jointed antennae ; it is the cly- 

 peus that is so much elongated and not the trophi, and the 

 palpi are 4-jointed. 



My friend Mr. Haliday having found a female specimen of 

 our insect on some rocks near the harbour of Donaghadee in 

 Ireland, established it as a genus in the Entomological Ma- 

 gazine, and gave it the name of 



Geranomyia unicolor. 

 Curt. Brit. Ent. pi. 573 ? , 

 and the 26th of last July we found both sexes in multitudes on 

 the sides of damp and shady rocks on the shores of the Shan- 

 non near Tarbert. 



I must here remark that the black line on the thorax is too 

 strongly marked in our figure, and it seems generally to vanish 

 after death, and totally disappears in the males. The other 

 species, 



G. MACULIPENNIS Curt., 



is rather larger than G. unicolor, and is of a lurid ochre, the 

 wings tinged with the same colour. It may be merely a variety 

 differing principally in colour, arising possibly from age. 



On the 1st of August, 1828, I took a female on the wet side 

 of a cliff at Ventnor in the Isle of Wight, where I have since 

 met with another specimen ; and Mr. Dale has captured spe- 

 cimens at Durdledoor rocks, which are covered at high water. 



The Plant is a variety o£ Saxifraga umbrosa (London Pride) 

 from rocks near the Lakes of Killarney. 



