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and rather plump. The fore wings were large, and had three discal 
(branch) veins, the third one forked near the middle, and scarcely 
visible near its base before forking. The stigma, or colored spot, was 
about three times as long as broad, and acute at each end. The hind 
wings were about half as long as the others, and quite narrow, with 
two simple discal veins. 
Let us now turn to the other species, the Apple-root louse ( Pemphi - 
gy,s pyri), and examine briefly its history and habits, and what rela¬ 
tion it has to the other speciest that has induced me to speak of the 
two together. 
This species was originally described by Dr. Fitch, in 1851, as 
Eriosoma pyri , (1855) transferred by him to Pemphigus, because the 
third vein of the fore wings of his specimens were simple, and not 
forked. Mr. Walsh in volumo 1, of the Proceedings of the Entomo¬ 
logical Society of Philadelphia and in The Practical Entomologist 
(1866), declared the two species to be distinct. Tn the latter, he states, 
in answer to a correspondent from Pennsylvania: ‘Aou think that the 
Aphis that causes warts- or knots on the roots of young apple trees in 
the nursery is the same insect on the T Vooly Aphis that lives on the 
twigs. You are, undoubtedly mistaken, for they do not even belong 
to the same genus, much less to the same species. The Wooly Aphis 
is Eriosoma lanigera , the Apple root Aphis is Pemphigus pyri 
In his first report, as acting State Entomologist (1868),. he repeats 
this declaration emphatically, and proceeds, not only to give the dif¬ 
ferences between the characters of the two species, but also of their 
habits; contending, after Blot, that the former is exclusively northern, 
while the latter is more southern. He also states in reference 
to the wooly Aphis: “It is now, however, pretty clearly ascertained 
to have existed on the continent of Europe from time immemoiial, 
. and it probably emigrated thence to England on imported apple trees.” 
It is proper to add, that up to this time Mr. W alsh had not succeeded 
in obtaining any winged individuals of the apple loot Aphis, but had 
relied imnlicitly on Dr. Fitch's description. Not only is it much less, 
but does not even belong to the same genus, being a true species of 
Eriosoma , with the third vein of the fore wings forked. The authors, 
upon making this discovery, came to the very reasonable conclusion 
that Dr. Fitch was mistaken in believing his specimens belonged to 
the apple-root louse; that they must have been stray specimens which 
had in some way become intermixed with the specimens of the lattei 
species. They also argue from the habitats of the two species (the 
root louse and Wooly Aphis), and from the fact that this works on 
the roots, while the Sch. lanigera works on the trunks and branches; 
that the American species is not identical with the European, and 
that the latter is unknown in the United States. I his article was in 
great part transferred by Prof. Riley to his first annual report (1869), 
without any dissent to the views there expressed; but in his thiid le- 
port (1871), as heretofore stated, we find him expressing the opinion 
that the two species are identical, or at least but varieties of one 
species, and that the former (Sch. lanigera) was imported into Europe 
from this country, wnich opinion, I believe, he still entertains. 
One or two more facts and suggestions, and for the present I will 
leave the matter with the reader, that he may form his own con¬ 
clusions. 
