FISHERIES, GAME AND FORESTS. 359 



the elm leaf beetle under control. The relatively few grubs caught on a sticky band 

 are but a drop in the bucket compared with the mass which complete their trans- 

 formations. It is worse than useless to attempt to control this or any other 

 insect by boring a hole in the trunk of a tree and inserting therein a compound 

 of any nature. The tree is weakened and unless the chemical be powerful enough 

 to kill the tree, the insects are not affected. 



I^ag or I^as^ef Worm. 



Thyridopteryx cpliemeraeformis Haworth. 



This insect is limited in this state to the southern portion of the Hudson river 

 valley and to the islands about New York. It has been recorded as far north as 

 Yonkers and Mt. Vernon. It is a species of considerable economic importance to us 

 despite its limited range in the state, and in New York city and vicinity it finds 

 ample opportunity to inflict considerable damage on valuable trees. It manifests a 

 great liking for certain evergreens and as these are usually killed with one defolia- 

 tion, there is need of watching them closely. A study of the insect shows it to be 

 one of the most interesting forms in our native fauna. 



The conspicuous larval cases or bags reveal the identity of the depredator or 

 excite the wonder of the curious, and examples of these are received yearly, some 

 with accounts of serious injury, and others with a query as to the nature and origin 

 of the curious structures. 



Description. The larval case or bag of this insect is usually the first to attract 

 notice. It is a fusiform structure from an inch and a half to two and one-half 

 inches long and in fall and winter it is firmly attached to a twig by a broad band 

 of silk, as shown at figure 10 on plate 1. The form of the bag is quite characteristic 

 but as this shelter is covered with particles of bark, pieces of leaves, leaf stems, etc., 

 from the tree on which the larva feeds, its appearance may vary considerably. A 

 female case cut open in late fall or winter presents the appearance shown at figure 

 11, plate 1. Within is the black pupal case and inside that there is a soft yellowish 

 down and a large number of yellowish eggs, a few of which are shown enlarged on 

 the same plate at figure 12. The appearance of the young larva and the cases formed 

 a little later are exceedingly well shown at figures 13, 14 and 15 on plate I. Special 

 attention should be called to the harmony in color existing between the small cases 

 and the portion of the twig upon which they occur, due, as determined by Mr 



