June, ’IS] 
GILLETTE AND BRAGG: APHIS BAKERI, ETC. 
329 
This species feeds chiefly upon composites, but not exclusively. 
Our records of food plants and dates of capture are as follows: 
Place 
Date 
Collector 
Food Plant 
Form 
Fort Collins 
11- 4-07 
L. C. Bragg 
Tanacetum balsamita 
alate, apterous 
Fort Collins 
Woods Hole, 
6-15-09 
L. C. Bragg 
Achillea sp. 
apterous 
Mass. 
7- 3-09 
L. C. Bragg 
Anthemis sp. 
alate 
Fort Collins 
10-28-10 
L. C. Bragg 
Carduus sp. 
apterous 
Fort Collins 
5-14-11 
L. C. Bragg 
Senecio sp. 
alate 
Fort Collins 
5-16-11 
L. C. Bragg 
Urtica 
alate, apterous 
Boulder 
6-24-11 
L. C. Bragg 
Onosmodium sp. 
alate 
Fort Collins 
9-30-11 
L. C. Bragg 
Ambrosia 
artemisifolia 
apterous 
La Porte 
9-29-11 
L. C. Bragg 
Eupatorium sp. 
alate, apterous 
Palo Alto 
4-26-12 
H. Morrison 
Amsinckia 
intermedia 
alate 
California 
1-11-13 
W. M. Davidson 
Helianthus 
apterous 
Fort Collins 
1-27-15 
L. C. Bragg 
Cineraria sp. 
alate 
Fort Collins 
3-29-16 
L. C. Bragg 
Bursa bursa 
alate 
Fort Collins 
6 - 1-16 
L. C. Bragg 
Apple 
alate, apterous 
Fort Collins 
12- 5-17 
L. C. Bragg 
Malva sp. 
alate, apterous 
Other plants on which this species has been taken in Colorado are 
Carrot, Chrysanthemum, marguerite, Carum, heliotrope, Phacelia and 
Lithospermum. 
The types described by Kaltenbach were taken from Helichrysum 
chrysanthemum, “Balsamite,” Anthemis tinctoria and Achillea patarmica 
in Europe, all composites. In northern Colorado this species often 
occurs in special abundance on Ambrosia artemisifolia, and Erigeron 
canadense, and, of the cultivated plants, Tanacetum balsamita and 
•Cineraria. 
A peculiar thing in connection with this louse, which is very notice¬ 
able where it is abundant upon the plant, is the hard excretion which 
seems not to be liquid, and which gives a frosted appearance to the 
foliage upon which it accumulates. 
In addition to what is given in the above key, it might be stated 
that this is the smallest of the group considered, large alate individuals 
seldom exceeding 1.35 mm.; the antennae is nearly as long as the body; 
the cornicles taper slightly in the alate form, and more noticeably in 
the apterous form, from the base towards the tip. We have found no 
evidence of either sexual forms or eggs. 
Aphis viburnicola Gillette (Fig. 12, 6-12) 
Aphis viburnicola Gill., Entomological News, 1909, p. 280. 
This is an abundant species every spring and fall upon the snowball 
bushes, {Viburnum), and to the present, has eluded all attempts to 
