464. = MINNESOTA STATE HORTICULTURAL SOCIETY. rhs 
pes 
this white cottony material. If we observe more closely we find at ii 
one end a brown or black, saddle-shaped, leathery disk with some Bais 
wrinkles on its back. This is the body of the insect which secreted : 
the white fibers, covering from one to two thousand eggs ofa pink © 
color. The young lice emerge early in July and are very active fora . 
short time, running about from place to place in search of a place 
in which to settle. The maleis much smaller than the female and a 
ceases to grow in 4 few weeks, becomes stationary and changestoa iS | 
pupa inside the larval skin, which is covered with a thick coat of — . . 
wax. The males emerge in August or September. The fertilized aa 
females continue to grow until autumn, when they migrate to the Saat 
twigs and remain dormant over winter. In the spring their bodies pet. 
become convex, and the eggs, which are deposited from the middle eee bi 
of May till July, are rapidly developed. " a 
A number of other scales closely allied to the two just mentioned on 
are also found in our state. Se si 
All members of the citrus family,as oranges, etc.,as well as many \ 
other greenhouse plants, are greatly injured by the Hemispherical 
scale (Lecanium hemisphericum ). 7 
The Willow or Cottonwood-scale (Chionaspis salicis. LINN. 
The trunks and branches of our cottonwood, poplars and willows 
are often covered with innumerable, very small, papery and snow- te 
white scales, which give them the appearance of being whitewashed. 
Fic. 4.—Willow or Cottonwood-scale. é 
: 
Two forms of scales can be distinguished, the large female scale, 
more or less pear-shaped, with two small overlapping cast skins at 
the apex, and a small oblong male scale, with three ridges running 
lengthwise and with only one larval skin. The purple eggs are laid 
during autumn, and they hatch about the first of June into small 
oval and flattened lice, whieh are very active, and quickly spread 
over the tree upon which they-.were born. : 
The Elm-tree White-scale. (Chionaspis Americana. JOHNSON): 
Many of the fine elms inthe vicinity of St. Paul and Minneapolis 
are infested with small scales closely 
resembling those on poplars and willows 
but less conspicuous, as the bark of the 
elm is also spotted with white and, there- 
fore, better adapted to conceal them. 
These scales are found both on the trunk 
and twigs and, though in some cases 
very numerous, have as yet caused no 
visible injury to the trees. Figure five 
shows both sexes of this scale. 
Fic. 5.—Elm-tree White-scale. 
