SWARM OF HAWK-FLIES. 



625 



All tlie Hawk-flies are extremely variable in their numbers, 

 sometimes being very scarce, while at other times they appear 

 in swarms. There is a notice in the ' Entomologist,' vol. iv. 

 page 357, by Mr. C. Home, in which the numbers of these 

 insects are mentioned. 



'At Margate, on August 24, 1869, there came a great 

 number of these insects, so as to attract the notice of all 



1. Syrphus (or Scfeva) pyrastri. 

 4. Tachiua grossa. a. Do., head, 

 of male. 



2. Conops macrocephalus. 3. Tachina ferox, 



b. Do., antenna. c. Conops macrocephalus, abdomen 



visitors. Many specimens were taken, among which I have 

 identified Syrphus balteatus, 8. decorus, S. tcmiiatus, S. topia- 

 rius, and Eristalis tenax. The wind was then blowing from 

 the east, and it was very hot weather. The pier at Ramsgate 

 on the same day was almost covered with them, and everyone 

 said that they came from the Channel. After this the wind 

 was from inland, but it was too fresh and breezy for many to 



s s 



