THE HARLEQUIN CABBAGE-BUG : ITS DISTRIBUTION". 267 



boundary of Maryland. Uhler, in liis List of Hemiptera of the Region 

 West of the Mississippi, gives the following statement of its distribu- 

 tion : — 



" It inhabits Guatemala, Mexico, Texas, Arizona, Indian Territory, 

 California, Nevada, Colorado, and from Delaware to Plorida and 

 Louisiana. In the Atlantic region it seems to be steadily but slowly ad- 

 vancing northward. Its introduction into Maryland has been effected 

 since the late war, and now [1875], it is known as far north as the 

 vicinity of the Pennsylvania boundary-line in Delaware. In the Mis- 

 sissippi Valley it appears to be equally common, particularly in the 

 States of Illinois and Missouri." 



Its presence in Colorado as a serious injury to the farmers, and its 

 occurrence at Denver, where it was observed by Prof. Uhler, proves its 

 capability, although a Southern species, of sustaining itself even north 

 of the isothermal line of 40° Fahr. Allowing it this range, will admit 

 of its future extension into the Western States, at least over the 

 southern portions of Minnesota and Wisconsin, and eastward, entirely 

 over the States of New York and Vermont, the southern portions of New 

 Hampshire and Maine, a large portion of the Province of Ontario, up to 

 48° of north latitude, and the Province of Quebec southward of a 

 line north of the St. Lawrence River. This extension, we believe, will 

 be only a question of time, for its progressive march seems as steady, 

 although not so rajjid, as was that of the Colorado potato-beetle. Its 

 distribution over the northern portion of the United States cannot 

 but operate as a serious check uijon the culture of cabbage, and may 

 prove even more disastrous than the introduction of tlie cabbage but- 

 terfly, Pieris rapm. for the ravages of this latter insect are more within 

 our control, and arc also limited by parasitic agency. 



Injuries. 



The harlequin cabbage-bug is not confined to cabbages, but feeds 

 also on turnips, radishes, mustard and other cruciferous plants, and 

 Prof. Uhler has informed me that it also attacks curcubitaceous plants. 

 Mr. J. W. Moore, of Johnson Town, Northampton county, Va.,* to 

 whom I am under obligation for information concerning this insect, 

 has written me that last year it entirely destroyed the cabbage crop in 

 his neighborhood, and that the present year, few cabbages having been 

 set out, it has made sad havoc with his ruta-bagas, upon which they 

 were still preying as late as the first of November. In only one in- 

 stance have we heard of its attacking other plants than those belong- 

 ing to the order of CruciferEe — that noticed in the commencement of 



*The valuable notes upon injurious insects, together with examples of rare species, from 

 time to time communicated to me by Mr. Moore, show a cultivated observation of insects 

 and their habits, and a highly commendable desire to aid in the advancement of economic 

 entomologj'. 



