116 



il-U'OUL' OF TIIK KNTO.MOLOClCAIi SECTION 



Characters of 

 the pupa 



Persistenct: 

 in following 

 its victims 



fourth, iiftli and sixth abdominal segments, and one of intermediate breadlli on the seventh 

 abdominal segment. The eighth abdominal segment terminates in a coronet of six teeth, in 

 colour shining brown becoming darker at the tips. The dorsal pair are smallest and close 

 togetlier, the ventral pair next in size and wider apart and the lateral pair longest and 

 arising from almost the same level as the dorsal pair. Ventrally placed to this coronet of 

 teetli are two rows of small teeth, from two to four in each row, together forming an 

 interrupted transverse row. These teeth are of unequal size and vary in their relative 

 sizes in different specimens. 



Tabanus lieitiula, Palisot de Beauvois 

 Plate III., figs. 1-5 and 7 



Tliis is the most connnon and most widely distributed tabanid found in the Anglo- 

 Egyptian Sudan, and is the one most frequently accused of causing the death of camels. 

 On the White Nile it occurs as far north as Dueim, and stray specimens, brought in by 

 cattle, have occasionally been taken in Khartoum. Often it will board a river steamer, 

 and being, like other seroots, a vicious blood-sucker, will drive any animals travelling 

 on the barges nearly frantic with pain. It will follow cattle and other animals long 

 distances — on one occasion, after walking straight inland from the river for five hours 

 without seeing a single seroot of any kind, numbers of this tabanid in company with 

 Tabanus ditseniatus, Macq., were found attacking a buffalo which they had doubtless 

 followed from some fly belt near or through which the animal had passed. Males are 

 rarely seen, though single specimens will sometimes board a river steamer, and early in 

 June, 1909, some twenty or thirty of this species were noticed on flowering shrubs on 

 Khor Felus, Sobat Eiver. 



Gorged females were taken in May, on cattle grazing near Bor, and placed in a breeding- 

 cage with a dish containing grass and weeds growing in mud and water. They were fed 

 on sugar and water, and a few egg-masses were obtained. A single egg-batch was taken 

 in May on a blade of grass overhanging a dried up water pool near Kanissa wood-station, 

 and a number of egg-masses was collected early in July from grasses and weeds 

 overhanging rain-pools at Gebelein. 



The eggs are placed by the female fly on the upper side of a blade of grass or some 

 similar plant and, with the exception of the single egg-mass taken at Kanissa wood-station, 

 all those found were overhanging water. An unfinished egg-mass in plan resembles an 

 arrowhead. The eggs are closely applied to each other and left bare, so that the mass 

 can easily be seen when freshly laid, owing to its shining white to yellowish-white colour. 

 Prior to hatching, the egg-mass becomes darker. 



The eggs obtained in the breeding-cage were laid on May 24-25, and hatched on 

 May 29. The larvtB were placed in glass basins containing mud, growing grass and water, 

 and offered the expressed stomach contents of female ticks — Bhlpicephalns simiis — taken 

 from a dog. They fed readily on this until June 11 when they were placed in clean river 

 sand and water and their diet changed to mosquito larvae. These mosquito larv* were 

 either killed or laid living on the wet sand out of reach of the water, when the tabanid 

 larvae were able to kill them. In water, the mosquito larvte were too active to be caught. 

 On July 1(), their food was changed again to freshly-killed and bruised earthworms, and 

 these they also ate readily. While still young they became vicious cannibals, and con- 

 sequently each larva had to be given a separate dish. They were brought to Khartoum 

 on July 19, and, a few days later, it was noticed that the majority were not taking their 

 food. They were then nearly, if not quite, full grown, so it was thought that they had 



