37 



species of Clisiocampa. Many of the trees (or more properly boshes, 

 as they seldom, if ever, attain sufficient size to be properly called 

 trees) were killed through repeated defoliation by the larvae of this 



insect. A resident farmer stated that the caterpillar- were much more 

 numerous some years than others. This beautifully marked larva was 

 first found some 5 miles up Platte Canyon, back of Denver, but 

 < tccurred there very sparingly. It eats only oak and confines it- attack- 

 to young, tender leaves. -It seem- unable to eat old leaves, and so 

 most mature before they become tough. 



The eo;^- are laid near the ground on twig- at the base of the t: 

 and have no frothy covering a- have many species of the genus. The 

 larvae arc gregarious when young, but soon scatter and feed singly. 

 They spin no web. 



Trypeta galls on Bigdovia. — At the little station of Platte Canyon, 

 at the mouth of the canyon of that name, there are great number- of 

 Bigelovia. During the latter part of May every bush bears a number 

 of white fluffy but compact galls as big as hazelnuts. Often there 

 will be found 50 or more galls on a sino-le bush. Thev are caused by 

 a beautiful little fly, Adura bigloviae Ckll. At this time of the year 

 the pupae may be found within the gall-, snugly incased in cells at the 

 center. The pupa is about 5 mm long by 3 mm wide, oval in shape, and 

 varying in color from pale yellowish red to brown, probably according 

 t<> age. The insects emerge by the first of June, the first ones appear- 

 ing in the breeding cage on May 28. 



The cabbaui loopt r(Phisia ftrassicae Riley).— In the early part of July 

 a few observation- were made on injurious insects of the garden in the 

 vicinity of Delta, in Delta County. Several intere>ting item- were 

 noted. The larva of Plusia ftrassicae was the main pest, and seemed to 

 be quite omnivorous, eating not only the cabbage, but also the potato, 

 turnip, rutabaga, lettuce, and table and sugar beets; it was also 

 found on a prickly poppy-like plant locally called "wild lettuce." 

 While the cabbage in some cases was almost ruined, it was on the 

 lettuce and potato, especially the lettuce, that the most damage was 

 done. Quite large rield< of potatoes were so eaten by this larva a- to 

 tie easily noticeable at a considerable distance, having something the 

 appearance of bring badly infested with the potato beetles. On the 

 lettuce the damage was extreme. In some cases the plant was entirely 

 devoured and was eaten out below the surface of the ground. The 

 rutabaga- and peas were also badly eaten. The larvae occurred in 

 various stages, some very -mall and other- full grown. Specimens 

 were sent to Dr. Dyarat Denver to be reared, but they failed to trans- 

 form. An inflated larva was preserved. 



77" cottonwood leof-heriU (Lina scripta Fab.). — The willow- in the 

 eastern foothills visited by Dr. Dyar and myself were badly int. - 

 with a Chry.-omelid larva which often occurred in sufficient number- to 

 completely skeletonize the leave- of large branches. The beetles were 



