36 



of injuiy by this spotted l^eaii beetle was observed near Fort Collins, 

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

 larvaj 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 fiea-heetle {Halt'ica hhnarginata 111.). — July 19 a collecting 

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

 canyon, the alders along the river were found to be infested hy ])eetle 

 larvffi which ate the upper side of the leaves, in some cases completel}^ 

 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 himarginata. 



The tent caterpUlar {Clklocampa fragUlx. 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 larvi\i of Oli><!<>c((nq)a 

 fragllls. 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 Dr. Dyar 

 failed to tind 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 severel}^ as the aspen. Over what area this 

 injury extended 1 can not say, having been unable to make sufficient 

 observations. In the vicinity of Cripple Creek the aspens were also 

 infested, but not nearl}' so badl}' as those on Pike's Peak. On reach- 

 ing the summit 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 })enumbed, fallen in the snow, there to die. 



The lilachorer i^Podosesia syrlng » 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 empt}' pupal 

 shells were protruding through the bark. 



The fruit-tree leaf -roller {Cacoicia argyrospila Walk.).^ — The leaves 

 of living ash trees were badl}^ infested with the larvae of this Tortricid. 



^1 neio tent eate7plUm' {Clwiocampa tigr/H Dyar). — The scrul) oak in 

 the eastern foothills, especiall}^ just west of Sedalia, between Denver 

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



