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be due to lack of fertilization, as the little wingless brown males occur 
in large numbers and freely copulate with the females during the fall. 
The cabbage louse (Aphis brassticce) seems to be a worse pest upon 
cabbages and ecauliflowers than the cabbage butterflies, P. rapw and 
P. protodice. 
The beet army worm (Laphygma flavimaculata), which ravaged the 
sugar-beet fields to such an alarming extent in the Grand Valley in 
the summer and fall of 1899, was almost entirely absent over the 
same area in 1900, in spite of the fact that the moths emerged in 
enormous numbers late in September for hibernation. They did 
occur in considerable numbers last year, however, in the vicinity of 
Rockyford, Colo., where sugar beets were being grown for the first 
time in large numbers for commercial purposes. The past summer 
the first brood of this insect appeared in considerable numbers, both 
at Palisade, in the Grand Valley, and in the Arkansas Valley in the 
vicinity of Lamar. It is now time for the second brood to be on in 
full force, but I have heard nothing of it yet. It looks as though 
another native insect, formerly unknown as a destructive species, had 
come to stay as an enemy to beet culture. 
The cabbage Plutella (P. cruc:ferarum).—A curious instance in the 
food habits of this insect was called to my attention the present sum- 
mer. Mr. H. E. Mathews, horticultural inspector for Delta County, 
sent me a quantity of leaves from small peach trees, with hundreds of 
small white cocoons upon them, with the statement that some new 
peach defoliator had appeared in an orchard in Delta County and he 
wished me to tell him what to do about it. I could not tell what 
the insect would turn out to be, but in a few days moths of the cab- 
bage Plutella appeared in large numbers, and I was almost as much 
puzzled as before. I told Mr. Mathews the ordinary food habits of 
the insect, and then he explained that the year previous the ground 
in this orchard had been allowed to grow up to a wild mustard, and 
that the weeds had been thoroughly kept down this summer. . The 
moths, doubtless, hatched there in large numbers and, not finding 
their natural food plants, deposited eggs upon peach leaves, upon 
which the larve developed. (Photographs of the cocoons of this 
insect upon peach leaves were exhibited. ) 
The thistle butterfly (Pyramets cardui) was unusually abundant 
throughout the State while fruit trees were in bloom, so that many 
inquiries were made as to the significance of this insect in such 
numbers. 
_ The bean ladybird (Hpilachna corrupta) does considerable damage 
to the foliage of beans, particularly wax beans, near the foothills of 
the east slope of the mountains every year, but the degree of destruc- 
tiveness varies much. The present season the injuries have been 
more severe than for several years past. It is also difficult to combat 
on account of the beans being very susceptible to injury from the 
