MIGRATIONS EASTWARD. 89 



It entered South-Western Wisconsin in 1862. In 1864 and 

 1865 it crossed the Mississippi River, entering Illinois from 

 the eastern borders of North Missouri and from Iowa " upon 

 at least five different points on a line of two hundred miles." 

 Thence it has travelled eastward at the rate of a little over 

 seventy miles a year. In 1867, it had appeared in Western 

 Indiana and South-western Michigan, and in 1868 had gen- 

 erally overspread Indiana and appeared in Ohio. From the 

 statements of Mr. Riley, it appears that this insect entered 

 Canada in July, 1870, and swarmed in 1871 between the 

 St. Clair and Niagara rivers ; the same year, Dr. Trimble 

 reported its presence in Pennsylvania, and in 1871 it also was 

 seen in New York. A Southern column advanced eastward 

 into Kentucky, arriving there probably in 1869. In 1872, 

 it had reached Lancaster County, Pa., and Cattaraugus 

 County, New York; and in 1873, according to Mr. Riley, it 

 had pushed to the extreme eastern limit of that State. It 

 was reported in the same year to have been seen in the Dis- 

 trict of Columbia, according to the Monthly Report of the 

 Department of Agriculture for* August and September, 1873. 

 In 1874, it became well established in Connecticut, New 

 Jersey, New York, Pennsylvania, Delaware, Maryland, and 

 Virginia (Riley's Seventh Report). 



In the summer of 1874, it appeared at Williamstown, 

 Mass., in small numbers, as I am told by Mr. J. S. Kingsley. 

 Its first appearance in the centre of this State was in Belcher- 

 town, where, I am informed by Mr. L. W. Goodell, "a sin- 

 gle larva was found July 15, and was apparently the last one 

 of a brood, as several hills of potatoes near were entirely 

 denuded of foliage, and I could find no others, nor signs of 

 any, in that or other fields of potatoes in the vicinity, although 

 I searched carefully. The one taken was placed in a box of 

 earth, and immediately buried itself and was transformed 

 to a beetle eleven days thereafter. About this time I found 

 and killed some fifty of the beetles on the same potato-patch, 

 which were probably a part of the same brood. No more of 

 the larvoe were seen for about three weeks, when they made 

 their appearance in large numbers in several fields." 



At the same time I learned from Mr. Isaac L. Ham of 

 Winchendon, Mass., a town about eighty miles west of Bos- 



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