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of injury by this spotted bean beetle was observed near Fort Collins, 

 where a large patch of beans had nearly eveiy leaf killed by the 

 larvae of this insect. At that time, in July, the beetles were in the 

 pupal state, hanging- in great numbers on the underside of the leaves. 

 Professor Gillette stated that no effective remedy for them was 

 known, the insect being able to withstand anything that did not 

 injure the plants. The adult beetles are said to exude a tiny drop of 

 yellow liquid of a pungent odor from each knee joint when disturbed. 

 The insect is discussed by Professor Gillette in Bulletin 19 of the 

 Colorado Experiment Station. 



The apple flea-beetle (Haltica Mmargvnata 111.). — July 19 a collecting 

 trip was made up Platte Canyon. At Pine Grove, some miles up the 

 camion, the alders along the river were found to be infested by beetle 

 larvae which ate the upper side of the leaves, in some cases completely 

 skeletonizing them. An attempt was made to rear the adult beetle, 

 but other duties interfered and it was not successful. A number of 

 the larvae were collected, however, and Mr. Schwarz identities them as 

 those of Haltica Kmarginata. 



The tent caterpillar (Clisiocampa fragiUs Stretch). — On July 20 the 

 ascent of Pike's Peak was made, and here occurred the worst case of 

 forest depredation by insect foes that ever came under my observation. 

 The aspens were completely defoliated by the larvae of Clisiocampa 

 fragilis. The imagos were then issuing, and, even in the middle of 

 the day, they swarmed about the tops of the leafless trees like bees, 

 thousands and thousands of them. The cocoons literally covered the 

 twigs, one a foot in length often containing a dozen or more of them. 

 So completely defoliated were the trees at this place that Mr. Dyar 

 failed to find a single leaf with which to supply an aspen-feeding Not- 

 odont larva which he was rearing. Our observations were made 

 mostly at 9,000 to 12,000 feet altitude. The willow and rose were also 

 attacked, but not nearly so severely as the aspen. Over what area this 

 injury extended I can not say, being unable to make sufficient observa- 

 tions. In the vicinity of Cripple Creek the aspens were also infested, 

 but not nearlv so badly as those on Pikes Peak. On reaching the sum- 

 mit of the peak we found hundreds of the moths lying dead or helpless 

 on the snow banks. They had evidently flown up from the timber 

 line, and, becoming benumbed, fallen in the snow, there to die. 



The lilacborer {Podosesiasyrmgai Harr.). — In West Denver numbers 

 of ash trees were completely killed by this Sesiid borer. The trees 

 were small, about 6 inches in diameter, and dozens of empty pupal 

 shells were protruding through the bark. 



The fruit-tree leaf -roller (Cacascia argyrospila Walk.). — The leaves 

 of living ash trees were badly infested with the larvae of this Tortricid. 



A new tent caterpillar {Clisiocampa tigris Dyar). — The scrub oak in 

 the eastern foothills, especially just west of Sedalia, between Denver 

 and Colorado Springs, was badly infested with the larvae of this new 



