TRANSMISSION OF MALARIA BY ANOPHELES IN NORTH AMERICA 
127 
also feeds on man (Hill 1934). Townsend 
(1934) thought it was probably unimpor¬ 
tant as a vector in Brazil. From his studies 
in Panama, Rozeboom (1938a) concluded, 
“A. bachmanni can be infected with human 
malarial parasites, but its preference for 
animal blood renders it harmless so far as 
malarial transmission in Panama is con¬ 
cerned. ’ ’ 
Further studies of A. bachmanni will be 
required before its relative importance can 
be determined in the different regions of its 
distribution. 
18. Anopheles (Nyssorhynchus) darlingi 
Root 1926 
a. Experimental infection. Bennaroch 
(1928), in Venezuela, dissected 83 A. dar¬ 
lingi that had fed on a malarial patient of 
unknown type, with negative results. 
There are no records of its experimental 
infection with P. vivax, P. falciparum or 
P. malariae. 
b. Infection in nature. The high sus¬ 
ceptibility of A. darlingi to natural infec¬ 
tion is indicated by the following results of 
dissection of wild mosquitoes caught in dif¬ 
ferent regions: 
Natubal Infections 
Authorities 
Place 
Mosqui¬ 
toes 
Infected 
Boot (1926) 
per cent 
Venezuela 
114 
10.5 
Bennaroch 
(1931) 
Davis (1931) 
Brazil 
220 
22 
Davis & Kumm 
Brazil 
240 
28.7 
(1932) 
Kumm (1932) 
Brazil 
5 
60 
Shannon 
Brazil 
9 
(1933) 
Kumm (1940) 
British 
Honduras 
32 
31 
c. Epidemiological. Bennaroch (1931) 
reported that A. darlingi was the most 
prevalent anopheline during outbreaks of 
malaria in Venezuela from May to Decem¬ 
ber, 1930. It is considered as one of the 
most important vectors in several countries, 
including Brazil (Townsend 1934; De Be- 
zerra 1936; Pereira Barretto 1938) and 
British Guiana Giglioli 1938a, b). Komp 
(1940a) stated, “A. darlingi is the most 
dangerous vector of malaria in Brazil ex¬ 
cept the imported A. gambiae, and in 
British Guiana and Venezuela.” 
Ayroza Galvao and Pereira Barretta 
(1938), in Brazil, described 4 types of eggs 
of A. darlingi var. paulistensis. 
The conclusion is that A. darlingi is 
apparently an important and dangerous 
vector, but it should be studied for the 
identification of races and subspecies to 
determine more exactly its susceptibility to 
different species and strains of plasmodia. 
In this connection the recent discovery of 
this species in Guatemala and British Hon¬ 
duras is of special interest. 
19. Anopheles (Nyssorhynchus) oswaldoi 
Peryassu 1922 
There are no data on experimental infec¬ 
tions and only inadequate epidemiological 
data. The natural infections reported on 
A. oswaldoi, in Brazil, by Boyd (1926) were 
later referred to by him (1930e) as in A. 
tarsimaculatus. The conclusion is that the 
relation of A. oswaldoi to malaria has not 
been determined and should be investigated 
further. 
20. Anopheles (Nyssorhynchus) strodei 
(Root 1926) 
a. Experimental infection. Bennaroch 
(1928), in Venezuela, reported failure to 
find infection in 5 specimens fed on ma¬ 
larial parasites of undetermined type. 
P. vivax. Ayroza Galvao (1938), in 
Brazil, reported the feeding of 4 A. strodei. 
on a carrier of P. vivax gametocytes, and 
when dissected after 19 days at 19-24° C 
and 67-88 per cent relative humidity, two 
mosquitoes contained numerous mature 
oocytes in the stomach and sporozoites in 
the salivary glands. There are no data for 
P. falciparum and P. malariae. 
b. Infection in nature. Bennaroch (1928) 
failed to find natural infection in 22 A. 
strodei dissected in Venezuela. Ayroza 
Galvao (1938) reported that R. Correa ex¬ 
amined 174 female A. strodei taken in 
houses in Sao Paulo, Brazil, and found 2 
infected with oocysts in the stomach. 
