174 MOSQUITOES OF NORTH AMERICA 
the fact that the larve of this mosquito are not green, even when found among 
vegetation of that color until nearly full grown, after which, like the larve and 
pupe of Anopheles quadrimaculatus, they may be bright grass-green. These 
mites lived for several days on the larve, but when removed from them and 
placed in water, they soon sank to the bottom and died. . 
“Tt is possible that the bluish green mite of Culex abominator is a different 
species, for I have never found them of this color on Anopheles quadrimaculatus ; 
yet under similar circumstances the larve, pupe and freshly emerged adults of 
this mosquito are also bright green. It is certainly very probable that this mite 
destroys quite a good many mosquitoes, and it is unfortunate that they do not 
extend their operations throughout the season instead of only the early part. 
“ A good many species seem to be for the most part never or only very rarely 
attacked at all.” 
In considering the whole question of the effect of these mites it seems doubtful 
whether they destroy adult mosquitoes. Mr. Banks gives as a result of his ob- 
servations that mosquitoes that do carry mites do not seem to be inconvenienced 
by them. The mites, he states, can not live long out of the water, and can never 
complete their transformations. If extremely numerous their weight might 
hinder the flight of a mosquito, or they might take enough nourishment from 
the host to seriously weaken it. Mr. Banks’s observations have been made for 
the most part in the vicinity of Washington, where this mite infestation is rare. 
In their work on malaria in Algeria, the Sergents made a number of observa- 
tions upon these parasitic mites. They found there that the mites seem to occur 
only on Anopheles and never upon Culex or any other genus of mosquitoes. 
Their specimens were examined by Trouessart, who found them to be hexapod 
larve of hydrachnids which could not be determined in the larval condition 
but which probably belonged to the genera Fylais, Hydrodroma, Hydryphantes, 
or Diplodontus, whose larve are known to have parasitic habits but whose dis- 
tinctive characters are too slightly marked to connect them with the adult forms. 
Parasitized Anopheles were found by them from May to October, in the larval, 
pupal and adult condition. They found nine larve, two pups», twelve adult 
females and five adult males of Anopheles maculipennis so parasitized on the 
plain of Mitidja and in the valleys of Kabylia. They were able to follow in the 
laboratory the development of most of the parasitized larvee and these underwent 
their metamorphoses normally and did not seem to be inconvenienced by the 
hydrachnids. When the larva transformed to pupa the hydrachnids passed 
from the larval skin onto the pupa, and when the adult issued the mites left 
the nymphal skin and attached themselves to the winged insect. In their ex- 
perience these parasites are rarely single, and as many as ten were found upon 
the same insect. With the larve and adults they were found upon the abdomen ; 
with the pupe upon the dorsal portion, near the point where the skin splits to 
allow the adult to issue. They were attached to the host by their beaks and were 
observed to grow. The Sergents tried an experiment to see whether the larval 
hydrachnid can change its host. A female of Anopheles algeriensis was put into 
the same cage with two specimens of Anopheles maculipennis which carried 
numerous mites. The next day, upon the abdomen of the Anopheles algeriensis, 
found dead, they found a mite. From this experiment they concluded that these 
