600 THE ANIMAL PARASITES OF MAX 



(14) " Larvas cle la Calliphora limensis en fosas nasalis," 1855, 18 pp., F. Aguirre. 



(15) " Raro caso di parasitismo nell 'uomo dovuto alia larva di una mosca (Sarcophaga 

 affinis, Meigen)," Soil. d. Soc. Rom. per gli Stud. Zool., Roma, 1893, iv (5' 6 )> PP- 278-289, 



i pi., 3 figs., Giulo Alessandrini. 



(16) " Observations sur 1'espece de ver nomme Macaque (Oestrus)," Mem. Acad. Set- 

 far Hist., 1753, p. 72, F. Artur, 



(17) " Contribuicao ao estudo da biologia da Derniatobia cyaniventris" Trav. do lust, de 



1908. 



BITING-MOUTHED AND OTHER Noxious DIPTERA WHICH MAY BE 



DISEASE CARRIERS. 



[Amongst the division Brachycera (as meant in this work) we get several groups 

 of flies which, like the fleas and mosquitoes, are partially parasitic on man, the adults, 

 mainly in the female sex, being provided with a piercing mouth with which they 

 extract the blood of man and animals. The importance of these parasites is net the 

 mere fact that they feed upon our blood, but that they often carry germs from man 

 to man (tsetse-flies and trypanosomiasis, Tabanidce and anthrax). Amongst the 

 most important biting-mouthed Diptera in this section are the following : Tabanidce, 

 or gad-flies ; Glossince, or tsetse-flies ; and certain other Muscidce. Some of the 

 exotic Asilidcc and a few Leptidce also bite man. 



Family. Tabanidae (Gad-flies). 



[The Tabanidce have a broad, rather flattened body and a large head ; eyes united 

 in the male (except in some Chrysops). The antennas are composed of three seg- 

 ments, have the third joint composed of five to eight annul! in Chrysops they are 

 fairly long. The proboscis is projecting, and sometimes much elongated. The legs 

 are moderately stout. The venation of the wings is shown in fig. 415. 



[This family of gad or horse flies contains a great number of genera, all of 

 which may bite animals and man more or less severely. The female alone is 

 blood-sucking, the males feed upon the juices of flowers. The females deposit their 

 spindle-shaped white, black, or brown eggs on leaves, stems of plants that either 

 overhang or stand in water, and amongst rushes ; they are at first white, but become 

 brown or black. The eggs are laid in rounded, flattened or conical masses com- 

 posed of layers one upon the other. The larva? are carnivorous, feeding upon snails, 

 worms, other larve, etc., and have a distinct head ; they are cylindrical, com- 

 posed of eleven segments, the last with a vertical breathing pore, or the last two 

 segments may form a breathing tube. The majority taper to a point at each end, in 

 colour shining white or dull grey to yellowish, many of the larger specimens mottled 

 or banded with dark brown or black. The first seven abdominal segments are 

 encircled near the anterior margin with a ring of fleshy protuberances consisting of 

 a transverse dorsal ridge which may be divided by a depression into two. The 

 young larvae burrow into any soft vegetable substance ; they live both in the water 

 and under damp soil surrounding water, also in damp earth generally. The larvae 

 are not only carnivorous, but they are cannibals, frequently devouring their own 

 species. They may take more than a year to mature. 



[The pupae are found close to the surface of mud and earth, and are mostly dull 

 yellowish to brown in colour, with rows of spines on the distal third of each 

 abdominal segment ; the thorax bears a pair of ear-shaped spiracular structures, and 

 there are also six denticles at the apex of the abdomen. 



[A habit common to the adults of most of the Tabanidce of considerable economic 



