The Simulide of British Guiana. 249 
In 1878 in Hungary 20 to 30 cattle were killed daily in this manner and 
there are records of several children having met their death in the same way. 
In North Americathey are known as Buffalo and Turkey gnats attacking 
numerous kinds of mammals and birds. 
Travellers in Brazil speak of the Pium fly (S. amazonicwm) with dread. 
Bates (8) writes ‘“‘ the wretched chamber was darkened by a sheet of calico 
being stretched over the windows, a plan adopted here to keep out the Pium 
flies which float about in all shady places like thin clouds of smoke, render- 
ing all repose impossible in the daytime whenever they can effect an entrance.” 
Also further he declares that the Pium “so worrying in the River Soliminos 
is probably the same mosquito of the Orinoco described by Humboldt and 
which he referred to the genus Simulium.”’ 
According to H. Smith (9) the Pium of Tapajos and the Pium of Carua 
behave differently, which leads one to suppose that there may be several 
species all named Pium. 
Melville, to whom I am greatly indebted for the greater number of Simulium 
in my collection, speaks of these Pium flies as a very severe trial. “ Pium”’ 
is the Brazilian name while “‘ Cabouri”’ is the Arawak name applied to them 
in British Guiana. 
Melville describes them as frequent on the upper reaches of the Essequebo 
River with its branches the Rupununi and Siparuni and also on the large 
hinterland savannahs. Swarms of these flies follow travellers, biting human 
beings and animals but also apparently sucking the sweat from the skin 
more particularly of native women. These insects have a voracious enemy in 
the nature of a black and white wasp (probably Monedula signata). This 
wasp follows the Aboriginal Indian to obtain the Pium which it reduces to 
unconsciousness and leaves with its eggs as a food store. Melville describes 
the bite as extremely painful followed by an irritating swelling which may 
subsequently develop into a kind of chronic skin eruption. Mégnin in France 
has described a type of chronic psoriasis with subsequent vitiliginous patches 
due to numerous bites of Simulium reptans. 
One traveller who has spent much time exploring amongst the uplands in 
the interior of British Guiana tells me that these Pium flies at times are such 
a curse that it is absolutely necessary to wear face masks and gloves, more- 
over, it isimpossible to perform any but the scantiest of a morning toilette 
and that only under great discomfort. 
The material on which these notes are based consist of twenty-nine specimens 
of Simulium am .zonicum (Pium fly) and eleven specimens of a new species of 
Simulium. Mr. Rodway, the Curator of the Museum of the Royal Agricul- 
(8) The Naturalist on the River Amazons p. 364, 1895. 
(9) Hubert Smith, Brazil, the Amazons & the Coast, p. 334- 
