THE SIMULIDA OF BRITISH GUIANA. 
By K. 8. Wiss, M.B., B.S., B.Sc., D.P.H., Government BACTERIOLOGIST. 
During the past few years much attention has been paid to the Culicide 
of this colony and as a result of the work of Ozzard (1) of Aiken and Rowland 
(2) and of Aiken (3, 4, 5) excellent and accurate descriptions of the mosquitoes 
of British Guiana are to be found in the local publications. 
Other families of Diptera, however, which bite human beings and animals 
exist largely in this land and form in some parts at certain times of the year 
veritable pests. 
In view of the fact that great attention is being directed in all parts of 
the world to biting Diptera other than Culicide, it has become necessary 
and of interest to examine the specimens of this colony. 
The Muscide are represented by the ubiquitous Stomoxys caleitrans, the 
Hippoboscide by Olfersia. The Tabanide are very numerous and include 
species of the following families :—Dyspangonia, Chrysops, Diachlorus, 
Dichelacera, Bolbodimyia, Selasoma, Stibasoma, Tabanus and Lepidoselaga. 
The Simulide which forms the subject of this communication are repre- 
sented by two species, Simulium amazonicum described by Goeldi (6) anda 
new species described here for the first time. 
The Simulide comprise only one genus, Simulium, which, however, is world 
wide in its distribution. In Lapland they are sometimes extremely abundant 
in May and July preying upon man and animals. “It is not rare to see 
calves and sheep succumb to their bites. The Reindeer only escape the 
torture by taking refuge besides glaciers and on the summit of mountains. 
The Lapps preserve themselves and their Reindeer from these pests by living 
in the smoke of large fires”’ (7). 
The famous S. columbatczense is a severe and dangerous pest in the valley 
of the Danube. In May the swarms appear as dark clouds and woe betide 
man or animal which they meet. Thousands of bites, punctures and painful 
swellings, violent fever, asphyxia, convulsions and even death ensues. 
(1) British Guiana Medical Annual Vol. 12, 1904 p. 65 
(2) ” ” ss vs 1 —-14y 1906 p. 13 
(3) ” ” ” 9» 15, 1907 Pp. 59 
(4) ” ” ” ” ” 16, 1908 p. I 
(5) Timehri (grd Series), Vol. 1, Part II., p. 187, rout. 
(6) Memorias do Museu Goeldi IV. Os Mosquitos no Para, 1905, p 138. 
7) Parasites & Parasitic Diseases. Newmann & MacQueen, 1905. 
