68 



joint of the antennae and palpi ; it should be noted, however, that 

 the appearance of the latter is somewhat variable, and depends to 

 some extent upon the direction from which the palpi are viewed. 

 The eyes, which in life are often green, bronze-green, or blue, 

 are frequently marked with dark purplish, horizontal bands, 

 which vary in different species, and thus afford useful distinctive 

 characters ; as already mentioned, however, the markings and 

 original coloration of the eyes rapidly disappear after death, and 

 are usually entirely indistinguishable in dried specimens. 



With the exception of South Africa, where they do not 

 seem to be common,* species of Tabanus are to be found in 

 most parts of Africa ; in many localities the individuals of 

 certain species are often exceedingly abundant, and a pest to 

 domestic and other animals, besides frequently attacking man. 

 It may be remarked that collections made in previously 

 unexplored localities, though usually including several species of 

 Tabanus, do not necessarily result in the discovery of new forms, 

 since many species of this genus, such as T. tceniola, Pal. de Beauv, 

 (Plate VIII., fig. 61), and T. par, Walk. (Plate V., fig. 39), have an 

 exceedingly wide distribution ; thus, more than one species 

 originally described from a specimen from Cape Colony or Natal 

 has recently been received from Northern Nigeria or the Bahr-el- 

 Ghazal, while T. ditceniatus, Macq. (Plate XI., fig. 82), besides 

 occurring throughout the greater part of Africa, is also met with so 

 far away as North China. On the West African rivers, where 

 they are often called Mangrove-flies by Englishmen and English- 

 speaking natives, several species of Tabanus occur. Writing from 

 personal observation and experience in Northern and Southern 

 Nigeria, Mr. G. C. Dudgeon saysf : — " Tabanus is a genus which is 

 represented by a large number of well-marked species on the River 

 Niger and tributaries, as well as the other rivers along the coast. 

 The approach of a Tabanus is made known by its loud buzzing, 



* See p. 61. — Notes on Pangonia angulata, Fabr. 



t Of. G. C. Dudgeon, " Occurrence and Habits of Some Species of Human Biting 

 Flies belonging to the families Tabanidm and Muscidce (Olossina). from the West 

 Coast of Africa": Journal of Tropical Medicine, Vol. IX., No. 21, p. 327 

 (November 1, 1906). 



