TRANSMISSION OP MALARIA BY ANOPHELES IN NORTH AMERICA 
121 
been reported as follows: Darling (1910), 
in Panama, 1 mosquito; Davis and Shannon 
(1928), in Argentine, 3 mosquitoes. 
b. Infection in nature. Covell (1927) 
listed the reports of natural infections in 
northwestern Argentina as follows: “Pat¬ 
erson (1911), 16 out of 1549; Muhlens et 
al. (1925), 2 out of 62; Maza and Gonzales 
(1926), 2 out of 28; Davis (1927), 12 out 
of 435.” Later Covell (1931b) recorded 
two additional reports, namely, one by 
Benarroch (1928), in Venezuela, who dis¬ 
sected 103 mosquitoes with negative re¬ 
sults; and another by Davis and Shannon 
(1928), in Argentina, who dissected 369 
specimens and found 8 infected. Kumm 
and Ruiz (1928), in Costa Rica, dissected 
7 specimens with negative results. Wille 
(1933) found naturally infected mosquitoes 
in Peru. Vargas (1938) in Mexico reported 
that none of 801 salivary glands, but 2.28 
per cent of 526 stomachs, were infected. 
c. Epidemiological. Dyar (1928) con¬ 
cluded that it is probable that “A. pseudo- 
punctipennis is the principal vector of 
malaria in the drier regions.” According 
to Root and Andrews (1938), “it is known 
to be the main vector of northwestern Ar¬ 
gentina, but elsewhere it is believed to be 
of little or no importance. Careful workers 
in California, Panama and Venezuela have 
all concluded that in these regions this 
species is not a vector of sanitary impor¬ 
tance.” Herms (1919) stated that in Cali¬ 
fornia A. pseudopunctipennis is believed 
to be negligible as a factor in malaria. 
Williams (1937a) observed that although 
found in West Texas and Pecos Valley of 
New Mexico, it does not transmit malaria in 
our country. Earle (1936b), largely on 
epidemiological grounds, did not consider 
this species an important vector in Gra¬ 
nada. 
On the other hand Shannon (1933) 
stated that it appears that A. pseudopunc¬ 
tipennis Theobald is the only anopheline 
in the Runac Valley, Peru, and the only 
one in any abundance on the entire western 
slope of the Peruvian Andes. It is often 
numerous in houses and is considered to 
be a vector. Hoffmann (1932) concluded 
that A. pseudopunctipennis is responsible 
for endemic malaria over an enormous part 
of the center of Mexico, which is character¬ 
ized by a more or less dry climate and in¬ 
cludes high valleys 6000-7000 feet above 
sea level. He believed it to be the prin¬ 
cipal cause of winter malaria, particularly 
in the southern and western parts of the 
country. Hoffmann and Samano (1938) 
concluded that in all dry regions of Mexico 
A. pseudopunctipennis is not only the most 
important but almost always the sole vector 
of malaria. Giaquinto Mira (1936), in 
Guatemala, also believed that this species 
is the chief vector at high altitudes and 
that it seems to be able to transmit P. vivax 
better than P. falciparum. 
Because of the contradictory nature of 
the reports on the habits and the suscepti¬ 
bility to infection of A. pseudopunctipennis 
in various regions, perhaps attributable to 
varietal differences, it appears obvious that 
this mosquito will require additional in¬ 
vestigation to determine its exact status as 
a malarial vector throughout the wide range 
of its geographical distribution. 
7. Anopheles (Anopheles) xelajuensis 
De Leon 
There are no data available for this 
species, which is distributed in the high¬ 
lands of Guatemala, but according to Komp 
(1940b) it is so rare that it probably is of 
no importance as a vector of malaria. 
8 . Anopheles (Arribalzagia) apicimacula 
Dyar and Knab 1906 
a. Experimental infection. Benarroch 
(1928), in Venezuela, reported the feeding 
of 22 A. apicimacula on a patient with 
malaria of unkown type. The results were 
negative. 
P. falciparum. In 1936 a few A. apici¬ 
macula reared from larvae collected in Pan¬ 
ama were examined after feeding on human 
carriers of P. falciparum gametocytes. 
One mosquito which took blood containing 
2.8 gametocytes per 100 leukocytes was in¬ 
fected and had sporozoites in the salivary 
glands (Simmons 1937). There are no data 
for P. vivax and P. malariae. 
