DISTRIBUTION OF INSECTS 25 



plant. For this purpose a strong tin box is the best. If more than one 

 species is to be sent, it is well to divide the box and separate them be- 

 cause some caterpillars are so pugnacious that ihey will destroy others 

 and a few even those of their own kind. Some aquatic larvae will bear 

 transportation very well if packed in damp sphagnum moss, though some 

 of the more delicate forms would have to be put in vials containing 50% 

 alcohol. When sending packages containing liquids through the mails, 

 the government regulations should be observed. Insects are classed as 

 merchandise and sent at the rate of one cent an ounce. The sender's 

 name and address should appear on the upper left hand corner of the 

 package in order to facilitate its identification. 



Dealers in entomologic supplies. For the convenience of the 

 novice the addresses of a few dealers are given. 

 A. Smith & Sons, 269 Pearl st. New York, N. Y. 

 John Akhurst, 78 Ashland place. Brooklyn, N. Y. 

 M. Abbott Frazar, 93 Sudbury st. Boston, Mass. 

 Entomological society of Ontario, 429 Wellington st. London, Ont. 



DISTRIBUTION OF INSECTS 



The continued introduction of insect pests from other countries and 

 their spread and destructiveness in this land have resulted in considerable 

 attention being given to this important subject. While it is undoubtedly 

 true that many insects can not be excluded from the United States, the 

 rigid inspection at ports of entry by California agents has resulted in the 

 stoppage and destruction of many species before they could threaten any 

 industry by extensive ravages. 



Importance. The importance of knowing the actual distribution of 

 injurious insects has hardly occurred to many. Isothermal lines have 

 been indicated over this country and present some interesting curves, 

 but the temperature does not entirely control though it undoubtedly 

 greatly influences the distribution of insects. Degrees of moisture, 

 variations in soil and other features also have their effect. In deter- 

 mining the physical limitations of one species, we gain some idea of 

 those governing others. New York state possesses a most important 

 port of entry, many ships unlading at New York city varied cargoes 

 from all parts of the world. The long and low-lying Hudson river 

 valley offers a natural pathway from this port into the state for such 

 species as find our climate congenial. A number of important insect 

 pests have already established themselves in this valley and are spreading 



