38 MISC. PUBLICATION 336, U. S. DEPT. OF AGRICULTURE 
Anopheles atropos has been infected experimentally with malaria 
parasites (/22), but it is of doubtful importance as a transmitter of 
the disease. | 
This species is dark brown, with few markings. The palpi are 
faintly spotted with white scales or entirely dark. The dark spots 
on the wings are inconspicuous or lacking (pl. 5, /’), and the legs are 
without distinct white knee spots at the tips of the femora, which 
are usually visible in walkeri and quadrimaculatus. Examination 
for the knee spots is best made against a dark background, the speci- 
men being viewed in different positions. Light reflections from the 
bristles or scales should not be confused with pale scaling. The 
characters of the male terminalia are similar to those of walkeri. In 
the larva, which was first described by Hinman (74), the outer clypeal 
hairs have only a few branches, the inner hairs are sparsely feathered 
near the tip, and the antepalmate hairs of segments 4 and 5 are usually 
single. 
ANOPHELES WALKERI Theob. 
This usually rare species breeds in fresh-water marshes containing 
aquatic vegetation. It has been taken in light traps in fairly large 
numbers at Zellwood, in the vicinity of Lake Apopka, Orange County, 
Fla. (36), at Reelfoot Lake, Tenn. (89), and at Wabasha, Minn. (45). 
The species has been recorded from Sumter County, Ga. (72), Crowley, 
La. (9, 107), Bondurant, Ky. (2), and Scott and Little Rock, Ark. 
(85, 142). It has also been collected by the writers at Orlando and in 
Volusia County, Fla. It has recently been taken in Mississippi, South 
Carolina, and North Carolina (table 1). The specimens listed by Dyar 
(51) from Terrebonne, La., were later identified by Hinman (74) as 
Anopheles atropos. The species has been reported from most of the 
Northern States from New Hampshire to Minnesota and Kansas, and 
in southeastern Canada (cf. 100). 
A study of specimens from Florida has shown some larval char- 
acters distinct from those of specimens obtained in New York State 
(33). Matheson and Hurlbut (//9) have since reported that both 
forms occur in the vicinity of Ithaca, N. Y. Specimens from each 
State have been infected experimentally with malaria parasites (J04, 
11S), and one specimen infected with the parasites in nature has been 
reported from Bondurant, Ky., in the vicinity of Reelfoot Lake (2). 
The adults are readily attracted to light traps at night and the females 
to human hosts both in the daytime and at night (36, 45, 89). The 
breeding places and the resting places of adults are usually difficult 
to locate (2, 45, 89). The adults seem to prefer to remain on the 
emergent vegetation in the breeding areas. Matheson and Hurlbut 
(179) and Hurlbut (8S) found that two distinct types of eggs were 
deposited by this species, “summer” and “winter” eggs, and they con- 
cluded that overwintering occurred, at least in the North, in the egg 
stage. 
The females of this species from Florida are very dark. They 
usually have narrow but distinct white rings on the palpi and white 
knee spots at the tips of the femora. The wing spots (pl. 5, #) are 
less pronounced than in quadrimaculatus. In the larvae the inner 
clypeal hairs are set close together and are minutely feathered toward 
the tip, hair 1 of the prothorax is branched from the base, and hair 0 
of the abdominal segments shows more development than in either 
