328 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 11 
APHIS BAKERI AND SOME ALLIED SPECIES 
C. P. Gillette and L. C. Bragg 
In our aphid studies we have often been puzzled in the placing of 
several rather closely allied forms that might be grouped around Aphis 
hakeri on account of their resemblance to this species. Probably there 
are other species that will fall in to this same group, but they are not 
known to us now. 
The species treated in this paper all have short cornicles, in most 
cases, little, if any, longer than the hind tarsi and cylindrical in form. 
The cauda is rather short and broad, and in most of the species de¬ 
cidedly short and blunt. The antennae are shorter than the body with 
the third joint heavily set with tuberculate sensoria; joint 4 also has 
sensoria, usually somewhat tuberculate, and joint 5 may or may not 
have sensoria aside from the permanent one near the distal end. 
The filament varies to a considerable extent in length in the different 
species, but never is shorter than joints 5 and 6 taken together in the 
alate forms. 
We have been able to separate the species we have studied by the 
following key: 
Key for Alate Viviparous Forms 
Cornicles smooth, not having transverse rows of ridges or chitinous points.. helichrysi 
Cornicles having many transverse rows of chitinous points. 
A. Hind tibise with numerous sensoria. 
a. Sensoria on distal half of tibia (absent on fall migrants). vihurnicola 
b. Sensoria on proximal half of tibia (also on tibia of apterous viviparous form, 
but not on males). sensoriata n. sp. 
AA. Hind tibiae without sensoria. 
Beak not surpassing hind coxae. hakeri 
Beak surpassing hind coxae... crateegifolice 
Aphis helichrysi Kalt. (Fig. 12, 1-5) 
Aphis helichrysi Kalt., Monographic der Pflanzenlause, 1843, p. 102. 
Aphis myosotidis Koch., Pflanzenlause, 1857, p. 57. 
Aphis helichrysi Koch., Pflanzenlause, 1857, p. 135 (not this species). 
Aphis marutae Oest., Aphididae of Minn., 1887, p. 57. 
Brachycaudus helichrysi , V. d. Goot., Zur Systematik der Aphiden, 1913, p. 97. 
Brachycaudus helichrysi, V. d. Goot., Kenntnis der Hollandischen Blatt-Lause, 1915, 
p. 256. 
The above list of the more important papers treating of this species, 
gives the synonymy as we see it. We have Aphis helichrysi and A . 
myosotidis from Europe as determined by Van der Goot, and a large 
collection of what we have been considering to be marutce on a variety 
of host plants, and we are unable to separate them from one another, 
so we think they all should fall under helichrysi Kalt. 
