114 
MALARIA 
the first to report the infection of A. 
crucians with P. falciparum, a fact which 
was confirmed by King (1916b) and Root 
(1924b). 
P. malariae. Several investigators 
(Beyer, Pothier, Couret and Lemann 
1902b; Root 1924b; Mayne 1932; Boyd and 
Stratman-Thomas 1933a) have attempted, 
with negative results, to infect A. crucians 
with P. malariae. 
In 1927 Barber, Komp and Hayne re¬ 
viewed the data available on infectivity 
experiments with A. crucians, in which A. 
quadrimaculatus and A. punctipennis were 
used as controls, and concluded that the 
evidence did not indicate that “a given 
anopheles is more susceptible to one type of 
malaria parasite than another.” In 1934b, 
Boyd and Stratman-Thomas reported ex¬ 
periments in which susceptibility of A. 
crucians (inland variety) to P. vivax, P. 
falciparum and P. malariae was compared 
with that of A. quadrimaculatus. They 
concluded that there was a difference in the 
susceptibility of the mosquitoes to all three 
species of parasites, that of A. quadrimacu¬ 
latus being high even when the gametocyte 
density is low. A. crucians, on the other 
hand, was not infected when the gameto¬ 
cyte density was low; but, after the inges¬ 
tion of larger numbers of gametocytes, it 
was infected with P. vivax and P. falci¬ 
parum. None of the A. crucians was in¬ 
fected with P. malariae. Later Boyd, 
Kitchen and Mulrennan (1936) compared 
the susceptibility to P. falciparum of A. 
crucians, of the inland and coastal types, 
using A. quadrimaculatus as a control. No 
significant difference was noted in the sus¬ 
ceptibility of the two A. crucians varieties 
and both were relatively poorer hosts than 
A. quadrimaculatus. 
b. Infection in nature. In 1919 Mayne, 
in Louisiana, demonstrated infection in a 
wild specimen of A. crucians, and since 
that time various observers have reported 
other natural infections. In 1927 Barber, 
Komp and Hayne summarized as follows 
the results of the reported dissections in 
which the species of Anopheles were dis¬ 
tinguished and the stomach infections were 
recorded: A. crucians. 1446 dissected, 0.02 
per cent infected; A. punctipennis. 130 
dissected, none infected; A. quadrimacu¬ 
latus. 10,641 dissected, 1.1 per cent in¬ 
fected. 
Sporozoites have been found in the sali¬ 
vary glands of naturally infected A. 
crucians. 
c. Epidemiological. The epidemiological 
reports also are contradictory. According 
to Coveil (1927) A. crucians “is generally 
considered not to play an important part 
in the transmission of malaria, although 
Carter (1924) stated that it conveyed the 
disease effectually in the tidewater section 
of Virginia where malaria is bad, and this 
species is practically the only anopheline 
present. ” Barber, Komp and Hayne (1927) 
also referred to similar observations. Beyer 
and others (1902b) suspected A. crucians 
as being a vector of estivo-autumnal ma¬ 
laria, on epidemiological grounds, and Dyar 
(1922) stated that it is a dangerous carrier 
of malaria. 
Root (1924b) suggested that the brackish 
water strain may be an efficient carrier. 
Boyd and Stratman-Thomas in their report 
on the comparative susceptibility of the 
inland variety of A. crucians to infection 
stated, “A. quadrimaculatus is more sus¬ 
ceptible than A. crucians to the parasites of 
all three species of human malaria. They 
remarked that the greater epidemiological 
importance of A. quadrimaculatus in the 
propagation of malaria in the southeastern 
United States can be attributed to: (1) 
appreciable preference for human blood, 
(2) house frequency habits, and (3) high 
susceptibility to the malaria parasites. 
Contrasting differences on the part of A., 
crucians explain its relative unimpor¬ 
tance.” However, it is believed that the 
final decision as to its relative importance 
in all localities must be delayed until more 
exact information has been obtained con¬ 
cerning the characteristics of the different 
subspecies or varieties. 
3. Anopheles (Anopheles) Maculipennis 
Meigen 1818 
Dyar (1922) stated that A. maculipennis 
