TRANSMISSION OF MALARIA BY ANOPHELES IN NORTH AMERICA 
125 
another chapter, A. albimanus is considered 
as the principal vector in 17 countries. 
Hoffmann (1938a) observed that A. albi¬ 
manus is the chief vector in the tropical 
regions of Mexico that are humid, including 
both coasts but especially the Gulf coast, 
where it is abundant during the rainy 
season. 
There seems to be no doubt as to the fact 
that A. albimanus is an important trans¬ 
mitter of malaria in Central America and 
the West Indies, but in view of its apparent 
relative unsusceptibility to exotic strains of 
parasites in the experiments by Boyd, Carr 
and Rozeboom (1938), it appears that 
studies to determine its relative suscepti¬ 
bility should be made in the different 
regions where it is found. 
14. Anopheles (Nyssorhynchus) albi- 
tarsis Lynch-Arribalzaga 1878 
Acording to Coveil (1927), “Root (1926) 
considers that the species referred to by 
Brazilian entomologists as ‘braziliensis’ and 
*argyritarsis’ are really albitarsis, and 
further states that as far as he knows no 
dissections of the true braziliensis are on 
record. All their dissections for the above 
species are therefore given here.” 
a. Experimental infection. Covell (1927) 
stated, “Experimentally, Godoy and Pinto 
(1923) record having infected A. brazili¬ 
ensis but gave no details of their experi¬ 
ments, beyond stating that sporozoites were 
found. In nature they record the same spe¬ 
cies found infected, and Boyd records natu¬ 
ral infections of * argyritarsis.’ ” 
P. vivax. Ayrozo Galvao (1938), in 
Brazil, dissected 5 A. albitarsis which had 
fed 10-19 days previously on a earrier of 
P. vivax gametocytes and found none in¬ 
fected. 
P. falciparum. Rozeboom (1938a), in 
Panama, reported experiments in which 
100 A. albitarsis and 113 A. albimanus con¬ 
trols fed on human carriers of P. falci¬ 
parum gametocytes. Four of the A. albi¬ 
tarsis and 37 A. albimanus were found to 
be infected, showing oocysts in the stomach. 
There are no data for P. malariae. 
b. Infection in nature. Reports of natu¬ 
ral infections by various authors, as sum¬ 
marized by Coveil (1927), have been made 
by Stephens (1921), Godoy and Pinto 
(1923), Boyd (1926) and Kumm (1932). 
c. Epidemiological. Among observers in 
Panama it is the consensus that there are 
no epidemiological data to indicate that A. 
albitarsis may be of importance there; and 
Giglioli (1938a, b) believed it unimportant 
in British Guiana. However, in other loca¬ 
tions, particularly Brazil (Root 1926; 
Kumm 1932; Townsend 1934) and in Vene¬ 
zuela, it is considered an important vector 
of malaria. 
Additional studies will be required to dis¬ 
tinguish the varieties of A. albitarsis and to 
determine their relative importance in the 
transmission of malaria. 
15. Anopheles (Nyssorhynchus) ano- 
malophyllus Komp 1936 
There are no data regarding infection of 
this rare mosquito by malarial plasmodia. 
Because of the apparent rarity of this spe¬ 
cies, it seems probable that it is of no im¬ 
portance as a malarial vector. 
16. Anopheles (Nyssorhynchus) argyri¬ 
tarsis Robineau-Desvoidy 1827 
Covell (1927) commented on the reports 
dealing with A. argyritarsis as follows: 
“Owing to the confusion which exists with 
regard to the correct nomenclature of this 
species, it is extremely difficult to be certain 
whether the records relating to infection 
are accurate. Root (1926) holds that the 
‘Argyritarsis’ of Brazilian entomologists is 
really A. albitarsis Lynch Arribalzaga, and 
the records of Godoy and Pinto, Boyd and 
Davis are therefore given under the latter 
species. ’ ’ 
a. Experimental infection. — P. vivax. 
Darling (1910), in Panama, failed to infect 
one specimen of A. argyritarsis fed on a 
patient with tertian malaria. 
P. falciparum. Darling (1910), in Pan¬ 
ama, failed to find infection in three mos¬ 
quitoes fed on patients with estivo-autumnal 
malaria. Bennaroch (1928), in Venezuela, 
reported negative results with 6 mosqui¬ 
toes. Earle (1936b), in Grenada, reported 
