338 ENTOMOLOGY 



have worked their way inland. Thus the common cabbage butterfly 

 (Pieris rapcz) , first noticed in Quebec about 1860, was found in the north- 

 ern parts of Maine, New Hampshire and Vermont five or six years later, 

 was established in those states by 1867, entered New York in 1868 and 

 then Ohio. Aphodius fossor followed much the same course from New 

 York into northeastern Ohio, as did also the asparagus beetle (Crioceris 

 asparagi) , the clover leaf weevil (Hyper a punctata) , the clover root 

 borer (Hylastinus obscurus) and other species. In short, as Webster has 

 pointed out, New York offers a natural gateway through which species 

 introduced from Europe spread westward, passing either to the north 

 or to the south of Lake Erie. 



Inland Distribution. Pieris rapes, the spread of which in North 

 America has been thoroughly traced by Scudder, reached northern New 

 York in 1868 (as above), but appears to have been independently intro- 

 4uced into New Jersey in 1868, whence it reached eastern New York 

 again in 1870; it was seen in northeastern Ohio in 1873, Chicago 1875, 

 Iowa 1878, Minnesota 1880, Colorado 1886, and has extended as far 

 south as northern Florida, but is apparently unable to make its way 

 down into the peninsula. 



The asparagus beetle, Crioceris asparagi, another native of Europe, 

 became conspicuous in Long Island in 1856, spread southward to 

 Virginia and westward to Ohio, where it was taken in 1886; it is fre- 

 quent now in Illinois and Wisconsin and is known in Colorado and 

 California. This insect, as Howard observes, flies readily, and may 

 be introduced commercially in the egg or larval stage on bunches of 

 asparagus. 



The clover leaf weevil, Hypera punctata, common over Europe and 

 most of Asia, was found in Canada some seventy years ago, has spread 

 into Mississippi, Texas, Utah and Idaho, and is present on the Pacific 

 coast also. 



The lesser clover leaf weevil, Phytonomus nigrirostris, introduced 

 from Europe into the United States, has spread steadily westward and 

 has now reached Illinois, where it has been common since 1919. 



Cryptorhynchus lapathi, a beetle destructive to willows and poplars, 

 and common in Europe, Siberia and Japan, was found in New Jersey in 

 1882 and in New York in 1896, though known for many years previously 

 in Massachusetts. It became noticeable in Ohio in 1901 , and is steadily 

 extending its ravages, being known now in Minnesota. 



From Colorado the well-known potato beetle (Leptinotarsa decem- 

 lineatd) has worked eastward since 1840, reaching the Atlantic coast, 



