ENTOMOLOGIST''S REPORT. 115 



fields and pastures new," because the mother insect never acquires 

 wings or any organs of locomotion, and has no choice but to deposit 

 ber eggs where she transforms. 



After a few days of wandering the worms attach their bags firmly 

 to twigs, never to leaves or leaf- stalks, which might be detached by 

 the winter winds, and securely closing the opening with silk, transform 

 to a brown, shelly chrysalis or pupae (Fig. 5, b J, of which that of the 

 male is much smaller than that of the female. Between two and three 

 weeks thereafter the final transformation takes place, the insect reaches 

 its perfect state. The male issues from the bag as an exceedingly 

 active, hairy black moth, with clear wings and feathered antennae 

 ( Fig. 5, dj. The female, on the contrary, is a mere bag of eggs, without 

 head, legs or wings fcj. She wriggles herself out of the pupa shell 

 to the bottom of the bag, where she is sought by the male. After pair- 

 ing she returns to the chrysalis and fills it full of eggs, intermixed with 

 some fibrous matter, and closes the lower end with the remains of her 

 body. The eggs, thus doubly protected with chrysalis case and bag, 

 liave no difficulty in surviving the winter, and from each bag from 150 

 to over 200 young worms will, under favoring circumstances, escape. 

 . Of natural enemies this insect has very few. Birds do not seem 

 to feed upon the larvae, nor be able to penetrate the cocoons to extract 

 the eggs. It has, however, three insect parasites which bear the some- 

 what formidable names of Catolaccus thyridopterigis, Hemiteles thyridop- 

 terigis, and Pimpla conguisitor. The first named of these, a small, 

 dark, four-winged fly, is the most important of the three, destroying 

 ■quite a considerable portion of the eggs. 



The conspicuousness of the Bag worm, and the wingless condition 

 of the perfect female, render it a comparatively easy task to keep it in 

 check by collecting and burning the bags and their contents during 

 the autumn or winter. On deciduous trees there is no difficulty in 

 securing every one, but on evergreens much more care must be taken 

 that none escape observation. When this preventive measure has not 

 been taken, spraying during June and July will be efficient for the 

 destruction of the caterpillars. For this purpose Paris green is said 

 by those who have tried both to be preferable to London purple for 

 use on both evergreens and deciduous trees. 



It has been considered somewhat hazardous to spray evergreens, 

 but Prof. Keffer, Horticulturist of the State Experiment Station at 

 Columbia, claims to have saved choice specimens of Colorado Blue 

 spruce and Irish juniper by two applications of a strong solution of 

 Paris green — one ounce to five gallons of water — and gives it as his 



