112 REPOBT OF THE ENTOMOLOGICAL SECTION 



reservoir. The remainder were put in a small tank in the Gordon College garden for 

 the use of which I was indebted to Mr. M. F. Simpson, Assistant Director of Education. 

 Mr. Addison, Assistant Engineer in the Gordon College Workshops, kindly undertook to 

 see that this tank was kept supplied with water. All those in the tank died within a 

 few days, apparently from the attacks of a fungus, for prior to death, the fish assumed 

 a light furry appearance on the shoulders, and swam aimlessly about. At the same time 

 a number of those in the reservoir died, showing similar symptoms, but how many could 

 not be determined as several kingfishers were in the habit of fishing in this water and 

 they may have removed some of the sickly fish. On my return from Dongola at the end 

 of May no G. dispar could be found by searching the edges of the reservoir, nor have any 

 been noticed since, so it is feared that they have all perished. It is possible, though, that 

 there are still some hundreds remaining, for the volume of water contained in the reservoir 

 is very considerable. 



It is difficult to understand why these fish brought up in April should liave perished, 

 while those caught in the previous September flourished for over four months in a stagnant 

 gudwal. Possibly some simple precaution, which should have been taken to ensure their 

 remaining in good health throughout their rather trying journey, was overlooked, and in any 

 case the species seems deserving of another trial for it is one of the few " small " fish which 

 occur in this country, and, judging from the numbers which exist in Klior Arbat, it is a 

 most prolific breeder. 



Blood-sucking flies other than Mosquitoes 



Blood-sucking As will be seen from the list given some forty-nine species of blood-sucking THptera 



flies other than o^j^gj. than mosquitoes are now known to occur in the Sudan. Of these, two tabanids. 



Mosquitoes 



one from Eagaa and Dem Zubeir, Bahr-El-Ghazal Province, and the other from the 

 Lado District, Mongalla Province, are as yet nameless, as the specimens taken were 

 not in sufficiently good condition to allow of an accurate description being drawn up. 

 A third nameless tabanid, from Malakal, is also possibly representative of a new species 

 near Tabanus fiisciqje^, Ric, but, up to the present, only very much rubbed specimens 

 have been captured. Descriptions by Mr. E. E. Austen of three new seroots, all from 

 the same locality, viz. Khor Arbat, Eed Sea Province, are embodied in this rejaort for 

 the convenience of those who may not have seen tlie publications in which they have 

 appeared. 



Of the small seroot, Tabanus xiifis, Jaenn., two forms occur, specimens taken at 

 Khor Arbat being invariably slightly larger and uniformly paler than those from other 

 localities (Plate I., figs. 4 and 5). 



Three of the species figured — Chri/aops fuscipennis, Ric. (Plate I., fig. 1), Tahanus 

 diftinctna, Ric. (Plate II., fig. 1) and Hiematopota ahysniiica, Surcouf (Plate I., fig. 2) — 

 do not, so far as is known at present, occur within the bounds of the Sudan, but have 

 been taken just over the borders. It has been thought advisable, however, to illustrate 

 them. 



Since the last Report of these Laboratories was issued, the name Tahanus focius, 

 Walker, has been sunk as a synonym of Tabanus tseniola, Pal. de Beauv. It will probably 

 be noticed that the closely-allied species, Tabanus variatns, Walker, has not been included 

 in the list of Sudanese blood-sucking Diptera. This is because I am convinced that it 

 is not a valid species. Mr. Austen, in his African Blood-sucking Flies, alludes to the 

 possibilities of these two species proving to be one and the same, and the examination 



