ii6 



THE AMERICAN ENTOMOLOGIST. 



for many months, not changing to pupa 

 until late the following spring. Harris's 

 assertion that it is douhlc-hrpoded has long 

 been doubted by careful observers and is 

 unquestionably disproved by Mi■^s Murt- 

 feldt's experiments. 



Owing to the longevity of the flies and 

 the different dates at which they emerge, 

 there is a succession of the larvs, covering 

 a period of from four to six weeks; but 

 they are all of the same brood, and when 

 once they have entered the ground, that is 

 the end of them for the season. 



The Rose Slug, like most other insects, 

 has a large number of natural enemies, 

 but these are not yet adequate to the task 

 of keeping it in check. The attention of 

 florists has, therefore, been largely directed 

 to the discovery of some reliable artificial 

 remedy. 



Various applications have been tried 

 with more or less success, among which 

 the most certain in its effects is whale oil 

 soap suds, made in the proportions of one 

 pound of the soap to eight gallons of water. 

 The objections to this remedy are that it 

 has a disagreeable odor and is liable to 

 discolor the opening buds. Dusting freely 

 with powdered White Hellebore has also 

 been tried with very good, success, and it 

 may be used in water by dissolving a 

 tablespoonful of the powder in two gallons 

 of boiling water. The Pyrethruin powders 

 have as yet been used only to a limited 

 extent, but with the prospect that thorough- 

 ly applied they would prove effectual. 

 Lime has long been used with satisfactory 

 results, especially if applied when the dew 

 is on the plants. 



Capt. E. H. Beebe of Galena, 111., wrote 

 some time since to the Gardeners Monthly 

 that he had found powdered sulphur ap- 

 plied when the leaves were wet, certain 

 destruction, and Miss E. A. Smith cor- 

 roborates his experience {Prairie Farmer, 

 May 4th, 1878). Wood ashes were strongly 

 recommended in the Country Gentleman for 

 June 13th, 1871. The Paris Green mix- 

 ture has been used with excellent results 

 on bushes where it was not desired to cut 

 or pluck the flowers, but in view of the 



other available means of destruction is 

 not to be recommended. All applications 

 should be made just at night, as they are 

 then more certain of coming in contact 

 with the insects. Something can also be 

 done to prevent the flies from maturing. 

 As the cocoon in which the larva hibernates 

 is very frail, and as the latter does not sur- 

 vive the rupture of the same, it follows that 

 many of the insects may be killed by thor- 

 oughly stirring and pulverizing the soil of 

 rose beds. Roses that are transplanted from 

 one locality to another should, before 

 setting, be immersed in a tub of water and 

 have every particle of soil washed from 

 their roots. By observing this precaution 

 newly-made gardens may be secured for a 

 long time against this worst enemy of the 

 fairest flower. 



THE COLORADO POTATO-BEETLE. . 



RETROSPECTIVE. 



Some sixty years ago, or in 1819, the 

 United States Government fitted out an 

 exploring expedition to the Northwest Ter- 

 ritories under the command of Major 

 Stephen H. Long. The zoologist of this 

 expedition was Mr. Thomas Say of Phila- 

 delphia, whose name has since become so 

 familiar to every entomologist. While on 

 this expedition, extending through 1819 

 and 1820, numerous specimens of a species 

 of beetle were found on the upper Mis- 

 souri, near the base of the Rocky Moun- 

 tains, which some four years later (1824) 

 Mr. Say described in a paper read before 

 the Academy of Natural Sciences, Phila- 

 delphia, under the name of Doryphora 10- 

 lincata, an insect that has since received 

 the common name of Colorado Potato- 

 beetle. 



At the time of its discovery, neither Mr. 

 Say nor any of his associates could have 

 had the remotest idea that this insect 

 would at some future day become one of 

 the greatest pests that ever afflicted the 

 farms and gardens of this country. Later 

 explorers, visiting the same regions of 

 country where Mr. Say originally found 

 the "ten-liners," discovered it feeding on 



