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NEW YORK STATE MUSEUM 



over the state. As the climatic conditions limiting their existence in 

 destructive numbers are not definitely known, it is proposed to give 

 some attention to this important subject, at least in an incidental way, 

 and ascertain the actual boundaries not only of the occurrence of an 

 insect, but at what point it ceases to be a destructive pest and also any 

 variations in the number of generations produced in different sections 

 of the state. After several years of study of these subjects, general 

 laws may be deduced that will be of considerable value in determining 

 where such imported pests as the elm-leaf beetle, elm-bark louse, leopard 

 moth, San Jose scale and others will be destructive. This knowledge 

 will not only enable us to state whether an insect will be injurious in cer- 

 tain localities, but it may also give valuable aid in our attempts to pre- 

 vent the introduction of insect pests and their subsequent spread over the 

 state. 



Life zones. A most valuable addition to our knowledge of factors 

 governing the distribution not only of animals but also of plants, has 

 been made by Dr Merriam and his associates in the United States 

 department of agriculture. As a result the boundaries of certain life 

 zones have been indicated with a considerable degree of accuracy. In 

 New York state three life zones occur, the upper austral, the transition 

 and the boreal. The upper austral includes the western end of Long 

 Island, Staten Island, the Hudson river valley to near Mechanicville and 

 an Area bordering Lake Ontario and including Lakes Oneida, Cayuga. 

 Seneca and some of the smaller bodies of water. The boreal is repre- 

 sented by a small area in the Catskills, a much larger one in the heart of 

 the Adirondacks. a small one near the foot of Lake Ontario, and another 

 of about equal size in the southwestern corner of the state. The pres- 

 ence of three life zones within our borders affords excellent facilities for 

 studying the effect of climate upon insect life. It is believed that some 

 attention to this line of work will prove not only of great scientific inter- 

 est, but will also have an important practical bearing. Dr Howard is of 

 the opinion that the imported elm-leaf beetle, the two asparagus beetles 

 and the San Jose scale will be confined to the austral life zones. So far 

 as known at present, they are thus limited in this state, though the com- 

 mon asparagus beetle has been taken by my assistant. Mr Banks, near Fort 

 Ticonderoga, This means either that the asparagus beetle can exist on 

 the border of the transition life zone or else that the upper austral extends 

 farther up the Hudson river than at first supposed. The following are 

 some of the native insects which Dr Howard places as austral species, 

 that is confined to the lower and upper austral life zones: Cicada killer. 



