BLOOD-SUCKING INSECTS AND TROPICAL DISEASES. 167 



H. B. M. Vice-Consul, states that it " is common in summer, and is found all 

 over the town, principally in room?," and that " its bite is very painful, espe- 

 cially to newcomers." In Ceylon, according to Mr. E. E. Green, a species of 

 Phiebotnmus is sometimes more troublesome even than mosquitoes. 



Tabanidse {Horse-flies or Breeze flies : in Great Britain certain species are 

 also known as Dun-flies, Clegs, and Struts ; sometimes called Gadflies : on the 

 Upper Nile termed t<erut-flies, and in West Africa Mangrove flies— a designation 

 however, which ako includes Tsetse-flies). 



As already stated, the enormous majority of blood-sucking Diptera belong 

 to this family, in which the blood-sucking habit is (with the possible exception 



Fig. 4.— Chrysops fixlssimus. Walker, $. Sicgapore, Borneo. 



(x 3.) 

 of certain species of Pangonia) universal in the female sex. The Tabanidse are 

 world-wide in their distribution, and are among the largest of all families of 

 Diptera, the total number of species described at the end of the year 1902 

 being no less than 1,540. The majority of the species that have hitherto at- 

 tracted attention by reason of their bloodthirsty habits belong to one or other 

 of the four principal genera, Tabanus, Pangonin, Hamatopota, and Chrysops. 

 Of these Tabanus includes 908, Pangonia 255, Chrysops 160, and Hwma- 

 topata 62 species. It is possible that more thorough knowledge may enable 



Fig. 5. — Tabanus africanus, Gray. 9 . Bahr-el-Ghazal to Natal. 



(+ 2.) 



