Nashville union and American. [volume] (Nashville, Tenn.) 1868-1875, 1875-06-24

cross; and Grand Duchess, say ten,
have Booth and other so-called outside
crosses. There are two with Lord
George cross through Lord Duke of
Airdrie, and one at least, With the
Grand Turk cross. OF thefew so-called
pure Duchesses, several are doubtful
breeders. OF the strictly pure"
bulls, toe United States may claim
four lone a doubtful breeder, and
Great Britain four-sevpn In all.
THE COLORADO POTATO BUG.
For nearly Of quite sixteen years
this beetle has been advancing, Or,
more strictly speaking, spreading over
the country from its native habitat,
the plains near the base of the Rocky
Mountains, where it was first discover
ed. Taking the ratio Of its progress
eastward for the first few years after
it was found, it would not have reach
ed the Atlantic coast until 1873; but
it has doubtless been helped along by
the railroads, specimens flying into the
car windows, and being carried miles
before they could escape.
This insect crossed the Mississippi
river from Iowa into Wisconsin in
1864, or the spring Of 1866, and has
consequently advanced more than one
hundred miles per annum IN a direct
line, instead Of about sixty, the rate
at which it moved through Nebraska
and Iowa. But It has at last reached
the Atlantic coast and abounds from
New York southwark for several hun
dred miles. Its progress through the
New England States is only a question
Of time, probably not extending be-
yond the present season.
Scientifically speaking, this pestifer-
Gus insect is styled DoTyphOra decemIi-
ueGta, OF the "tsn-Iined spearmaa. Mr..
Charles R. Dodge, Assistant Etomolo-
gist United States Department of Ag-
riculture, in a report made few days
ago, says Of the pest:
1t belongs to the family Of leaf-eat-
ing beetles ,chrys0meidg) and is one
of the largest Of the group. The per-
feet insect measures about half an
inch in length, is Of a thick oval shape
and of a yellowish cream color, with
ten dark brown or yellOwish lines run
ming lengthwise down the wing covers.
The Iead and thorax, or middle portion
Of the body, are of an Orange-b brown
color, spotted or marked with black.
1t has, IN addition to the wing covers,
a pair of pink wings, which lie folded
beneath and hidden except wGen the
insect Is In flight.
The eggs to the number of 1000 or
1000 and even more are deposited up
on the young leaves Of the potato in
clusters, containing from one to two
dozen in each. These hatch IN a few
days, and the young Larvae Immediately
90 to work upon he foliage. They ac-
quire their colJr in less than three
weeks. In color they are dark orange
red, the head black, and a black ring
on the first segment of the body, and
a double row Of black dots down each
side from the head to the end of theab-
domen. After arriving at maturity,
the larva 60 into the ground and
change to purple, and IN about ten
days or two weeks the perfect beetles
appear. They begin to pair in about
week. and on the fourteenth day the
female begins 20 deposit her eggs; 50
we may consider that it takes about
fifty days for the insect to 90 through
all its changes from egg to egg, though,
Of course, the time may vary a little
from differences IN temperature.
The Colorado beetle was discovered
in the West over so years ago, during
an exploring expedition to the Rocky
Mountains under Maj. Long. 1t then
lived upon the wild prickly solanium so
common in that region. By some
means or other 1t held its place in ma
ture. for it was not heard Of till s. or
40 years later, after the cultivation of
the potato had extended to the basa Of
the Rocky Mountains. 1t seemed TO
thrive on the new food plant, and at
once commenced its march to the East,
slowly at first, as the potato fields were
few and far between, but steadily, until
at last it began to attract attention
as a dangerous enemy to agricul-
ture. Mr.. Dodge states that it APP
peared in Nebraska about the
year 1859, two years later
spreading over Iowa, and about the
year 1865 reaching the Mississippi
Ten years later it strikes the Atlantic
coast, after sweeping over the States Of
Wisconsin, Michigan, Illinois, Indiana
Ohio, Kentucky, West Virginia, Penn.
sylvania, New York, New Jersey, Della.
ware, Maryland, the District of Column
bia and the northern portion Of Vir.
ginia, though its greatest rayages have
been almost VII lily confined to the
States north Of Mason and Dixon'i