64 THE REPORT OF THE No. 19 



obstruction to the directly westward, migration of insects from east to wes', broken only in the 

 State of New York and the country adjacent to the north and south shores of Lake Erie. Here 

 we have a huge gateway through which nearly or quite all species imported from Europe, land- 

 ing on our eastern seacoast, north of the mouth of the Potomac river at least, make their way 

 into the comparatively level country beyond It is barely possible that the valley of the Big 

 Kanawka river in West Virginia and Cumberland Gap may ofler passage ways for an occasional 

 species, but of this we have no proof as yet. In the Cordilleran system there do not appear 

 to be any such openings or gaps for the outflowing and spread of migrating species, except, pur- 

 haps, in extreme southern California and Arizona, a country so arid that few species can take 

 advantage thereof, if it really exists, hence, a separation in South or Central America usually 

 remains permanent, while in the case of the Appalachians, a species may work its way south 

 along the Atlantic coast to the Gulf, and in a comparatively short time mingle with the northern 

 branch that has made its way west to the great lakes and thence southward. 



Besides these, there are paths of migration from the north southward, but these are con- 

 fined to the tAvo mountain systems now under discussion. 



I will now take up each of these paths or trails of migration and give a few illustrations t'-- 

 make my points more intelligible. (See Map 1.) 



The imported cabbage butterfly, Pieris rapa-, as is well known, was flrst observed in the 

 vicinity of Quebec in 1860. From here it gradually spread south into New England and west 

 through New York, so that it actually invaded Canada from the United States in 1872, and a 

 year later, in the spring of 1S7S, it appeared at Cleveland, Ohio, in limited numbers.^ 



Many years ago one of the Dung beetles, Aphndiiis fussor L., which occurs in Europe, wa.s 

 introduced into the same section of country as the preceding, and like it spread southward into 

 New England, and is now only being found occasionally in northeastern Ohio, though it was 

 included in the list of Lake Superior species in 1878 by Hubbard and Schwarz, but not in the 

 1880 list of Reinecke anel Zesch of species found within 15 miles of Buffalo, New York. In 

 this case it evidently spread faster through Canada, but came to Ohio by the way of western 

 New York. 



The Asparagus beetle, Crioceris anparagi, introduced from Europe many years ago, first 

 appeared in Ohio in the northeastern portion of the state, precisely as it made its way into 

 Canada by way of western New York. Crioceris 12-pundatus has not yet been found in the 

 State of Ohio but is to be expected within a year or two. 



The clover leaf weevil, PJiytonomns prmctatus, and the clover root borer, HyUtstes ohscurus. 

 both imported from Europe and both first coming to notice in western central New York, were 

 first reported in Ohio in the northeastern counties. It is true that a single specimen of the 

 former was taken from the nop of a croir .-yhot in MirldgaH. in 1892.- Yet had it invaded 

 the State of Ohio from that direction the fact would have been shown by its presence in 

 the clover fields of the farmer. I found it abundantly at Chautauqua Lake, New York, in 

 August, 1888, and it must have entered Ohio a year, or at most two, afterwards. Ifc is true that 

 Mr. Duryjfound it near Cincinnati in 1892 and Mr. Hine in Lucas County the following year, 

 but it did not become noticeably abundant until long after the farmers in northeastern Ohin 

 were complaining of its attacking clover. The llylastes also was found about Cincinnati so^in 

 after its appearance in northeastern Ohio, but like the Phytonomns it was probably carried inti> 

 some of the tributaries of the Ohio river, possibly in northeastern Ohio, during the high waters 

 of spring and down stream, being left by the receding water with driftwood and other debris, 

 far back among the cultivated lands along the river itself. 



'Scudder The introduction and spread of Pieris rapa' in North America, 1860-1885. Mem. Boa. 

 See. Nat. Hist. Vol. IV., No. III. 



"^The Common Grmu of the U.S., Burrows and Schioarz : Bull. G, U. S. Dep. Agr. Div. Ornithology and 

 Mammology. 



