, 
1918.] BASHAMBAR Das: The Aphididae of Lahore. 209 
is about five times that of the base, while in A. mazdis it is hardly more than 
double. 
Svstematic.—The species described as A. maidis (Fitch) by Essig (Pom. Coll. 
Jour. Ent., vol. IV, No. 3, p. 791, 1912) is evidently Siphocoryne avenae; hence it is 
not ende in the literature above. 
I have also included A. sorghi (Theobald) as a synonym of this species. It was 
reported to attack the leaves and heads of Dura (Sorghum vulgare in the Soudan), 
and an account of the insect appeared in the First Rep. Wellcome Res. Lab. Khartoum, 
1904. Unfortunately the account is incomplete in certain respects, and the details of 
structure, on an otherwise excellent plate, are somewhat inaccurate. The total 
absence of secondary sensoria, as shown on the antennae of the alate female, would 
be remarkable if it is so. From the colour, form, and the relative lengths of the 
antennal articles it appears to be identical with A. maidis (Fitch), though Prof. 
Theobald thinks otherwise. 
A. adusta of Zehntner, described in 1001, is undoubtedly A. maidıs, according to 
van der Goot.' | 
Food plants and times of appearance.—In India this Aphid feeds-on the following | 
plants :— 
(1) Wheat (Triticum sativum) December-March. - 
(2) Oats (Avena) November-April. 
(3) Barley (Hordeum vulgare) January and February. 
(4) Maize (Zea mays) August-November. 
(5) Sorghum (Sorghum vuigare) June-October. 
(6) Bajra (Pannisetum tyboideum) September. 
GERT (Panicum colorenum) September-November and April. 
Sy; (Panicum crus-gali) March. 
(9) Dub grass (Cynodon dactylon) December. 
In the above months collections have actually been made of this species in the 
plains, and it is also apparent that it infests both the Rabi and the Kharif crops in 
the Punjab, and that there is hardly any time of the year when it is not to be met 
with. 
Life-history.—Elaborate experiments were undertaken by Dr. Forbes (Report of 
the State Entomologist of Illinois, 1905, p. 123) to determine the life-cycle in winter at 
Chicago, and similar experiments were made by Davis (loc. cit.) at Urbana, Il. No 
sexual forms could be obtained. It appears that in that country it has not been 
definitely ascertained how the species passes the winter, as its food-plants are not 
available then. In India there is no difficulty on this account, since some crop is 
always available, and the insect can pass from one plant to another very easily. 
Owing to an abundant food ur here one meets with very few winged forms at all 
: | [Aphis maidis, Fitch, has been put by the writer into the genus Siphonaphis, v. d. G., for the 
reason that it has distinctly swollen cornicles, together with the presence of lateral tubercles on the first 
and seventh abdominal segments (see v. d. Goot, Zur Kenntniss der Blattläuse Java’s, p. 67). Bd. Gal: 
