222 ENTOMOLOGICAL SOCIETY 



From our present information it seems that the spread of this 

 destructive insect is likely to be limited, for a time at least, by the 

 boundaries of the upper and lower austral zones ; and if future 

 observations prove that this supposition based upon so few ob 

 servations, it is true be correct, it will afford immeasurable relief 

 to the thousands of fruit-growers in New England, large portions of 

 New York and Pennsylvania, and the northern portions of the 

 lower peninsula of Michigan. 



The older history of the eastern spread of the Colorado potato- 

 beetle affords another exemplification. Potatoes are grown from 

 the northern limits of the transition zone in British America south 

 to the Gulf of Mexico. The Colorado potato-beetle, originally 

 an inhabitant of the transition zone in the West, and feeding 

 upon native solanaceous plants, spread straight east through the 

 upper austral zone to the Atlantic ocean. It spread to the north, 

 into the transition region, more slowly than towards the southern 

 boundary of the upper austral. The centre of the army travelled 

 the fastest, the north wing more slowly, and the south wing 

 still more slowly. The insect established itself for a series of 

 years, at least, at every point along the journey, and at many 

 points permanently. Reaching the northernmost limit of the 

 lower austral, however, it found its limit for a time, and in the 

 southern range of this species we find a very interesting study. 

 Bordering the southward extension of the Alleghanian fauna is 

 a downward loop of the upper austral zone which includes the 

 northeast corner of Alabama and the northwest corner of 

 Georgia. So accurately were the limits of the spread of this 

 species gauged to the limits of the upper austral that the only 

 points in the Gulf line of States where the species had established 

 itself as a crop pest were, until within the last year or two, in the 

 northeast corner of Alabama and the northwest corner of 

 Georgia.* 



The asparagus-beetle, Cr to certs asparagi, was brought over 

 from Europe and became noticeable on Long Island in 1856 to 

 1859. This insect spreads readily by flight and is carried, in the 

 egg state and as young larva, on bunches of the cuttings sent to 

 market. Its original spread was westward upon Long Island, 

 out into southern Connecticut, down through New Jersey and 

 eastern Pennsylvania, through Delaware and Maryland to Wash- 



* In April, 1895, word was received of the occurrence of this species at 

 Charleston, S. C., where it is said by Mr. H. M. Simons to have been 

 destructive in 1894. Whether this is a permanent establishment will re 

 quire two or three gears' test; but at all events the restriction has lasted 

 manj years. The same may be said of Arkansas and northern Louisiana. 

 The insect occurs rarely at Auburn, Ala., and still more rarely, and only 

 upon native food-plants, in the Mesilla valley, in New Mexico. 



