10 MOSQUITOES OF NORTH AMERICA 
whole night, or obliged him to rise many times. The species, which I have ex- 
amined, is distinct from the common gnat, and appears to be nondescript. It 
approaches nearest to C. annulatus, but the wings are black and not spotted. 
And Captain Stedman in America, as a proof of the dreadful state to which he 
and his soldiers were reduced by them, mentions that they were forced to sleep 
with their heads thrust into holes made in the earth with their bayonets, and 
their necks wrapped round with their hammocks.” 
Quite the most interesting and really important of the observations upon 
mosquitoes by the older travellers, however, are those of Humboldt. The account 
is of general interest as indicating the conditions of life in the regions of the 
upper Orinoco and Magdalena rivers, and the hardships endured by the mission- 
aries who early visited those regions and who passed their lives there. It is also 
of special interest as a record of the observations of a very acute observer and 
reasoner. The observations were all original, and most of them were in direct 
contradiction to the views of former travellers and of the writers on natural 
history. The differentiation between the different species of biting flies, includ- 
ing mosquitoes, the discovery that different species inhabit different regions and 
bite at different times of the day and of the night, the fact that with certain of 
the residents of the upper Orinoco the existing fevers and other maladies were 
attributed to mosquitoes, the curious reasoning of the author on the possible 
carriage of disease by blood-sucking insects and the origin of fevers, and many 
other points in this chapter combine to make it one of very great interest in thé 
light of present knowledge of the Culicide of tropical regions. Parts of it, 
therefore, in free translation, are here presented. It must be kept in mind that 
Humboldt’s account deals with biting flies belonging to different families, and, 
in speaking of the separate forms, he uses the terminology customary in the 
Spanish-American countries. By the term “ mosquitos” he does not mean 
Culicide, but Simuliide; the mosquitoes in our sense are called “ zancudos” 
and “ tempraneros” ; the “ jéjen ” are minute Chironomid, now assigned to the 
genus Culicoides. In speaking of these forms collectively, Humboldt uses the 
term “ tipulaires,” which roughly corresponds to the group Nemocera, as now 
understood. In order to avoid confusion we have translated the French word 
“cousin,” which corresponds to our word “ mosquito,” by the word “ gnat.” 
“ After having spent two days at the cataract of Atures we were glad to be 
able to leave a place where the temperature of the air was generally 29° C. in 
the day and 26° C. at night. This temperature seemed still warmer than it 
really was. The lack of concurrence between the thermometer and our feelings 
should be attributed to the continuous irritation of the skin by the mosquitoes. 
An atmosphere filled with venomous insects always appears hotter than it really 
is. A Saussure hygrometer indicated in the shade (as usual) at the minimum 
in the day time (3 hours after noon) 78° 2”, at night at the maximum 81° 5”. 
.. » We were horribly tormented by the mosquitos and by the jéjen, venomous 
little flies or simuliums; at night by the zancudos, a species of large gnat or 
mosquito which is feared even by the natives. We began to have badly swollen 
hands and faces, and the inflammation increased from day to day until our 
arrival on the banks of the Temi. The means by which they try to escape from 
these little animals are very extraordinary. The good missionary, Bernardo Zea, 
who passes his life under the torments of mosquitoes, has constructed himself, 
